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HEPTAGONAL NUMBER

  • Heptagonal number
  • Type of figurate number constructed by combining heptagons

    mathematics, a heptagonal number is a figurate number that is constructed by combining heptagons with ascending size. The n-th heptagonal number is given by

    Heptagonal number

    Heptagonal number

    Heptagonal_number

  • Centered heptagonal number
  • Centered figurate number that represents a heptagon with a dot in the center

    other dots surrounding the center dot in successive heptagonal layers. The centered heptagonal number for n is given by the formula 7 n 2 − 7 n + 2 2 {\displaystyle

    Centered heptagonal number

    Centered heptagonal number

    Centered_heptagonal_number

  • 1000 (number)
  • Natural number

    heptagonal number. 1926 = 2 × 32 × 107. It is a pentagonal number. 1931 is a Sophie Germain prime. 1933 is a prime number and a centered heptagonal number

    1000 (number)

    1000_(number)

  • 6000 (number)
  • Natural number

    6000 (six thousand) is the natural number following 5999 and preceding 6001. 6028 – centered heptagonal number 6037 – super-prime 6047 – safe prime 6053

    6000 (number)

    6000_(number)

  • 7000 (number)
  • Natural number

    442 7246 – centered heptagonal number 7247 – safe prime 7260 – triangular number 7267 – decagonal number 7272 – Kaprekar number 7283 – super-prime 7291

    7000 (number)

    7000_(number)

  • Triangular number
  • Figurate number

    the nth m-gonal number and the nth (m + 1)-gonal number is the (n − 1)th triangular number. For example, the sixth heptagonal number (81) minus the sixth

    Triangular number

    Triangular number

    Triangular_number

  • Heptagon
  • Shape with seven sides

    regular heptagon. Apart from the heptagonal prism and heptagonal antiprism, no convex polyhedron made entirely out of regular polygons contains a heptagon as

    Heptagon

    Heptagon

    Heptagon

  • 71 (number)
  • Natural number

    an emirp and more generally a permutable prime. 71 is a centered heptagonal number. It is a regular prime, a Ramanujan prime, a Higgs prime, and a good

    71 (number)

    71_(number)

  • 2000 (number)
  • Natural number

    2273 – Sophie Germain prime 2276 _ centered heptagonal number 2278 – triangular number 2281 – star number, 2287 – balanced prime 2299 – member of a Ruth–Aaron

    2000 (number)

    2000_(number)

  • 8000 (number)
  • Natural number

    narcissistic number as 84 + 24 + 04 + 84 = 8208 8219 – twin prime with 8221 8221 – super-prime, twin prime with 8219 8233 – super-prime, centered heptagonal number

    8000 (number)

    8000_(number)

  • 4000 (number)
  • Natural number

    – pronic number 4166 – centered heptagonal number 4167 = 7! − 6! − 5! − 4! − 3! − 2! − 1!, number of planar partitions of 14 4169 – a number of points

    4000 (number)

    4000_(number)

  • 3000 (number)
  • Natural number

    octagonal number, dodecagonal number 3037 – star number, cousin prime with 3041 3046 – centered heptagonal number 3052 – decagonal number 3059 – centered

    3000 (number)

    3000_(number)

  • 106 (number)
  • Natural number

    natural number following 105 and preceding 107. 106 is a centered pentagonal number, a centered heptagonal number, and a regular 19-gonal number. There

    106 (number)

    106_(number)

  • 800 (number)
  • Natural number

    167. It is a Motzkin number. 837 = 33 × 31. It is the 36th generalized heptagonal number. 838 = 2 × 419. It is a palindromic number. There are 838 distinct

    800 (number)

    800_(number)

  • 900 (number)
  • Natural number

    movement in Myanmar 970 = 2 × 5 × 97. It is a sphenic number and a heptagonal number. 971 is a prime number, an emirp, a Chen prime, and an Eisenstein prime

    900 (number)

    900_(number)

  • 5000 (number)
  • Natural number

    triangular number 5167 – Leonardo prime, cuban prime of the form x = y + 1 5171 – Sophie Germain prime 5188 – centered heptagonal number 5189 – super-prime

    5000 (number)

    5000_(number)

  • 500 (number)
  • Natural number

    22 × 33 × 5. It is a largely composite number, an untouchable number, a heptagonal number, and a decagonal number. It is the sum of a pair of twin primes

    500 (number)

    500_(number)

  • 81 (number)
  • Natural number

    perfect totient number like all powers of three. a heptagonal number. an icosioctagonal number. a centered octagonal number. a tribonacci number. an open meandric

    81 (number)

    81_(number)

  • 148 (number)
  • Natural number

    N. J. A. (ed.). "Sequence A128919 (Numbers simultaneously heptagonal and centered heptagonal)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation

    148 (number)

    148_(number)

  • 300 (number)
  • Natural number

    number. 316 = 22 × 79. It is a centered triangular number, a centered heptagonal number, an Ulam number, and a member of one Tetranacci sequence. It appears

    300 (number)

    300_(number)

  • 700 (number)
  • Natural number

    centered heptagonal number, a happy number, a Harshad number, and a nice Friedman number since 736 = 7 + 36. 737 = 11 × 67. It is a palindromic number and

    700 (number)

    700_(number)

  • 34 (number)
  • Natural number

    is a Markov number. 34 is also the fourth heptagonal number, and the first non-trivial centered hendecagonal (11-gonal) number. This number is also the

    34 (number)

    34_(number)

  • 600 (number)
  • Natural number

    decagonal number and a zero of the Mertens function. 638 = 2 × 11 × 29. It is a sphenic number, a nontotient, a centered heptagonal number, and the sum

    600 (number)

    600_(number)

  • 400 (number)
  • Natural number

    a sphenic number, a nontotient and a Harshad number. There are 402 graphs with 8 nodes and 9 edges. 403 = 13 × 31. It is a heptagonal number, a zero of

    400 (number)

    400_(number)

  • 616 (number)
  • Natural number

    of the first two of these). 616 is a polygonal number in four different ways: it is a heptagonal number, as well as 13-, 31- and 104-gonal. It is also

    616 (number)

    616_(number)

  • 9000 (number)
  • Natural number

    – centered heptagonal number 9293 – Sophie Germain prime, super-prime 9316 – triangular number 9319 – super-prime 9334 – nonagonal number 9349 – Lucas

    9000 (number)

    9000_(number)

  • 197 (number)
  • Natural number

    + 23 + 29 + 31 + 37 197 is a centered heptagonal number, a centered figurate number that represents a heptagon with a dot in the center and all other

    197 (number)

    197_(number)

  • 253 (number)
  • Natural number

    amount of digits the 22nd triangular number. a star number. a centered heptagonal number. a centered nonagonal number. a Blum integer. a member of the 13-aliquot

    253 (number)

    253_(number)

  • 189 (number)
  • Natural number

    eighty-nine) is the natural number following 188 and preceding 190. 189 is a centered cube number and a heptagonal number. The centered cube numbers are

    189 (number)

    189_(number)

  • 235 (number)
  • Natural number

    preceding 236. 235 is a heptagonal number, a centered triangular number, and a Smarandache–Wellin number. It is a Harshad number in bases 6, 47, 48, 95

    235 (number)

    235_(number)

  • 112 (number)
  • Natural number

    twelve) is the natural number following 111 and preceding 113. 112 is an abundant number, a heptagonal number, and a Harshad number. There are 112 connected

    112 (number)

    112_(number)

  • 10,000
  • Natural number

    and a Harshad number in bases 2, 3, 4, 5, 6, 7, 8, 10, 13, 14 and 16 10009 = twin prime with 10007 10018 = centered heptagonal number 10080 = 21st highly

    10,000

    10,000

  • 7
  • Natural number

    number. Seven is the lowest natural number that cannot be represented as the sum of the squares of three integers. A seven-sided shape is a heptagon.

    7

    7

  • Pyramidal number
  • Figurate number

    946, 1222, 1547, 1925 (sequence A002412 in the OEIS). The first few heptagonal pyramidal numbers are: 1, 8, 26, 60, 115, 196, 308, 456, 645, 880, 1166

    Pyramidal number

    Pyramidal number

    Pyramidal_number

  • Natural number
  • Number used for counting

    natural-number results: subtracting a larger natural number from a smaller one results in a negative number and dividing one natural number by another

    Natural number

    Natural number

    Natural_number

  • List of recreational number theory topics
  • Polygonal number Triangular number Square number Pentagonal number Hexagonal number Heptagonal number Octagonal number Nonagonal number Decagonal number Centered

    List of recreational number theory topics

    List_of_recreational_number_theory_topics

  • Prime number
  • Number divisible only by 1 and itself

    A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that

    Prime number

    Prime number

    Prime_number

  • Perfect number
  • Number equal to the sum of its proper divisors

    In number theory, a perfect number is a positive integer that is equal to the sum of its positive proper divisors, that is, divisors excluding the number

    Perfect number

    Perfect number

    Perfect_number

  • 511 (number)
  • Natural number

    palindromic number and a repdigit in base 2 (1111111112). It is also palindromic and a repdigit in base 8 (7778). It is a generalized heptagonal number (sequence

    511 (number)

    511_(number)

  • Square number
  • Product of an integer with itself

    In mathematics, a square number or perfect square is an integer that is the square of an integer; in other words, it is the product of some integer with

    Square number

    Square number

    Square_number

  • Composite number
  • Integer having a non-trivial divisor

    A composite number is a positive integer that can be formed by multiplying two smaller positive integers. Accordingly, it is a positive integer that has

    Composite number

    Composite number

    Composite_number

  • 20,000
  • Natural number

    lifetime of 73.8 calendar years. 27405 = heptagonal number, hexadecagonal number, 48-gonal number, 80-gonal number, smallest integer that is polygonal in

    20,000

    20,000

  • Sierpiński number
  • Odd number with specific properties

    In number theory, a Sierpiński number is an odd natural number k such that k × 2 n + 1 {\displaystyle k\times 2^{n}+1} is composite for all natural numbers

    Sierpiński number

    Sierpiński_number

  • Fibonacci sequence
  • Numbers obtained by adding the two previous ones

    month, the number of pairs of rabbits is equal to the number of mature pairs (that is, the number of pairs in month n – 2) plus the number of pairs alive

    Fibonacci sequence

    Fibonacci sequence

    Fibonacci_sequence

  • Power of two
  • Two raised to an integer power

    A power of two is a number of the form 2n where n is an integer, that is, the result of exponentiation with the number two as the base and integer n as

    Power of two

    Power of two

    Power_of_two

  • 115 (number)
  • Natural number

    strip of seven rectangular stamps. 115 is also a heptagonal pyramidal number. The 115th Woodall number, 115 ⋅ 2 115 − 1 = 4 776 913 109 852 041 418 248

    115 (number)

    115_(number)

  • 9
  • Natural number

    9 (nine) is the natural number following 8 and preceding 10. Circa 300 BC, as part of the Brahmi numerals, various Indians wrote a digit 9 similar in shape

    9

    9

  • Congruent number
  • Area of a right triangle with rational-numbered sides

    In number theory, a congruent number is a positive integer that is the area of a right triangle with three rational number sides. A more general definition

    Congruent number

    Congruent number

    Congruent_number

  • Centered hexagonal number
  • Number that represents a hexagon with a dot in the center

    mathematics and combinatorics, a centered hexagonal number, or centered hexagon number, is a centered figurate number that represents a hexagon with a dot in the

    Centered hexagonal number

    Centered hexagonal number

    Centered_hexagonal_number

  • Catalan number
  • Recursive integer sequence

    they were previously discovered in the 1730s by Minggatu. The n-th Catalan number can be expressed directly in terms of the central binomial coefficients

    Catalan number

    Catalan number

    Catalan_number

  • 11 (number)
  • Natural number

    11 (eleven) is the natural number following 10 and preceding 12. It is the smallest number whose name in English has three syllables. "Eleven" derives

    11 (number)

    11_(number)

  • Abundant number
  • Number that is less than the sum of its proper divisors

    In number theory, an abundant number or excessive number is a positive integer for which the sum of its proper divisors is greater than the number. The

    Abundant number

    Abundant number

    Abundant_number

  • Smooth number
  • Integer having only small prime factors

    In number theory, an n-smooth (or n-friable) number is an integer whose prime factors are all less than or equal to n. For example, a 7-smooth number is

    Smooth number

    Smooth_number

  • Double Mersenne number
  • Number of form 2^(2^p-1)-1 with prime exponent

    In mathematics, a double Mersenne number is a Mersenne number of the form M M p = 2 2 p − 1 − 1 {\displaystyle M_{M_{p}}=2^{2^{p}-1}-1} where p {\displaystyle

    Double Mersenne number

    Double_Mersenne_number

  • 14 (number)
  • Natural number, composite number

    There are fourteen elements in a regular heptagon (where there are seven vertices and edges), and the total number of diagonals between all its vertices

    14 (number)

    14_(number)

  • Happy number
  • Numbers with a certain property involving recursive summation

    In number theory, a happy number is a number which eventually reaches 1 when the number is replaced by the sum of the square of each digit. For instance

    Happy number

    Happy number

    Happy_number

  • Squared triangular number
  • Square of a triangular number

    In number theory, the sum of the first n cubes is the square of the nth triangular number. That is, 1 3 + 2 3 + 3 3 + ⋯ + n 3 = ( 1 + 2 + 3 + ⋯ + n ) 2

    Squared triangular number

    Squared triangular number

    Squared_triangular_number

  • Lychrel number
  • Number, non-palindrome after repeated sum with reverse

    numbers exist? More unsolved problems in mathematics A Lychrel number is a natural number that cannot form a palindrome through the iterative process of

    Lychrel number

    Lychrel_number

  • Polygonal number
  • Type of figurate number

    In mathematics, a polygonal number is a number that counts dots arranged in the shape of a regular polygon. These are one type of 2-dimensional figurate

    Polygonal number

    Polygonal_number

  • Lucas number
  • Infinite integer series where the next number is the sum of the two preceding it

    numbers two terms apart in the Fibonacci sequence results in the Lucas number in between. The first few Lucas numbers are 2, 1, 3, 4, 7, 11, 18, 29, 47

    Lucas number

    Lucas number

    Lucas_number

  • Nonagonal number
  • Type of figurate number

    A nonagonal number, or an enneagonal number, is a figurate number that extends the concept of triangular and square numbers to the nonagon (a nine-sided

    Nonagonal number

    Nonagonal_number

  • Friendly number
  • Two or more natural numbers with a common abundancy index

    In number theory, friendly numbers are two or more natural numbers with a common abundancy index, the ratio between the sum of divisors of a number and

    Friendly number

    Friendly_number

  • Idoneal number
  • Mathematical concept in prime numbers

    power. In particular, a number that has two distinct representations as a sum of two squares is composite. Every idoneal number generates a set containing

    Idoneal number

    Idoneal_number

  • Palindromic number
  • Number that remains the same when its digits are reversed

    A palindromic number (also known as a numeral palindrome or a numeric palindrome) is a number (such as 16361) that remains the same when its digits are

    Palindromic number

    Palindromic_number

  • Harshad number
  • Integer divisible by sum of its digits

    In recreational mathematics, a Harshad number (or Niven number) in a given number base is an integer that is divisible by the sum of its digits when written

    Harshad number

    Harshad_number

  • Pell number
  • Number used to approximate the square root of 2

    starts with 0 and 1, and then each Pell number is the sum of twice the previous Pell number, plus the Pell number before that. The first few terms of the

    Pell number

    Pell number

    Pell_number

  • Mersenne prime
  • Prime number of the form 2^n – 1

    mathematics, a Mersenne prime is a prime number that is one less than a power of two. That is, it is a prime number of the form Mn = 2n − 1 for some integer

    Mersenne prime

    Mersenne_prime

  • Cube (algebra)
  • Number raised to the third power

    algebra, the cube of a number n is its third power, that is, the result of multiplying three instances of n together. The cube of a number n is denoted n3,

    Cube (algebra)

    Cube (algebra)

    Cube_(algebra)

  • Hexagonal number
  • Type of figurate number

    A hexagonal number is a figurate number. The nth hexagonal number hn is the number of distinct dots in a pattern of dots consisting of the outlines of

    Hexagonal number

    Hexagonal number

    Hexagonal_number

  • Regular number
  • Numbers that evenly divide powers of 60

    and have different names coming from their different areas of study. In number theory, these numbers are called 5-smooth, because they can be characterized

    Regular number

    Regular number

    Regular_number

  • Cyclic number
  • Integer whose multiples are digit rotations

    A cyclic number is an integer for which cyclic permutations of the digits are successive integer multiples of the number. The most widely known is the

    Cyclic number

    Cyclic_number

  • Kaprekar's routine
  • Iterative algorithm on numbers

    In number theory, Kaprekar's routine is an iterative algorithm named after its inventor, Indian mathematician D. R. Kaprekar. Each iteration starts with

    Kaprekar's routine

    Kaprekar's_routine

  • Tetrahedral number
  • Polyhedral number representing a tetrahedron

    A tetrahedral number, or triangular pyramidal number, is a figurate number that represents a pyramid with a triangular base and three sides, called a tetrahedron

    Tetrahedral number

    Tetrahedral number

    Tetrahedral_number

  • Stirling numbers of the second kind
  • Numbers parameterizing ways to partition a set

    particularly in combinatorics, a Stirling number of the second kind (or Stirling partition number) is the number of ways to partition a set of n objects

    Stirling numbers of the second kind

    Stirling numbers of the second kind

    Stirling_numbers_of_the_second_kind

  • Bell number
  • Count of the possible partitions of a set

    2,5,15,52,203,877,4140,\dots } (sequence A000110 in the OEIS). The Bell number B n {\displaystyle B_{n}} counts the different ways to partition a set that

    Bell number

    Bell number

    Bell_number

  • Quasiperfect number
  • Numbers whose sum of divisors is twice the number plus 1

    unsolved problems in mathematics In mathematics, a quasiperfect number is a natural number n for which the sum of all its divisors (the sum-of-divisors function

    Quasiperfect number

    Quasiperfect_number

  • Power of 10
  • Ten raised to an integer power

    the number ten; in other words, ten multiplied by itself a certain number of times (when the power is a positive integer). By definition, the number one

    Power of 10

    Power of 10

    Power_of_10

  • Lucky number
  • Integer filtered out using a sieve similar to that of Eratosthenes

    In number theory, a lucky number is a natural number in a set which is generated by a certain "sieve". This sieve is similar to the sieve of Eratosthenes

    Lucky number

    Lucky_number

  • Superior highly composite number
  • Class of natural numbers with many divisors

    In number theory, a superior highly composite number is a natural number which, in a particular rigorous sense, has many divisors. Particularly, it is

    Superior highly composite number

    Superior highly composite number

    Superior_highly_composite_number

  • Friedman number
  • Number that is the result of operation on its own digits

    A Friedman number is an integer, which represented in a given numeral system, is the result of a non-trivial expression using all its own digits in combination

    Friedman number

    Friedman_number

  • Untouchable number
  • Number that cannot be written as an aliquot sum

    In mathematics, an untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. That

    Untouchable number

    Untouchable_number

  • Evil number
  • Class of binary number

    In number theory, an evil number is a non-negative integer that has an even number of 1s in its binary expansion. These numbers give the positions of

    Evil number

    Evil_number

  • Octagonal number
  • Number of points in an octagonal arrangement

    In mathematics, an octagonal number is a figurate number. The nth octagonal number on is the number of dots in a pattern of dots consisting of the outlines

    Octagonal number

    Octagonal number

    Octagonal_number

  • Repdigit
  • Natural number with a decimal representation made of repeated instances of the same digit

    or sometimes monodigit is a natural number composed of repeated instances of the same digit in a positional number system (often implicitly decimal). The

    Repdigit

    Repdigit

  • Kaprekar number
  • Base-dependent property of integers

    In mathematics, a natural number in a given number base is a p {\displaystyle p} -Kaprekar number if the representation of its square in that base can

    Kaprekar number

    Kaprekar_number

  • Powerful number
  • Numbers whose prime factors all divide the number more than once

    every prime number p dividing m, p2 also divides m. Equivalently, a powerful number is the product of a square and a cube, that is, a number m of the form

    Powerful number

    Powerful number

    Powerful_number

  • Perrin number
  • Number sequence 3,0,2,3,2,5,5,7,10,...

    } The number of different maximal independent sets in an n-vertex cycle graph is counted by the nth Perrin number for n ≥ 2. The solution

    Perrin number

    Perrin number

    Perrin_number

  • Cake number
  • Concept in combinatorics

    In mathematics, the cake number, denoted by Cn, is the maximum of the number of regions into which a 3-dimensional cube can be partitioned by exactly

    Cake number

    Cake number

    Cake_number

  • Giuga number
  • Type of composite number

    In number theory, a Giuga number is a composite number n {\displaystyle n} such that for each of its distinct prime factors p i {\displaystyle p_{i}}

    Giuga number

    Giuga_number

  • Super-Poulet number
  • Type of Poulet number

    In number theory, a super-Poulet number is a Poulet number, or pseudoprime to base 2, whose every divisor d {\displaystyle d} divides 2 d − 2 {\displaystyle

    Super-Poulet number

    Super-Poulet_number

  • Semiprime
  • Product of two prime numbers

    In number theory, a semiprime is a natural number that is the product of exactly two prime numbers. The two primes in the product may equal each other

    Semiprime

    Semiprime

  • Euler number
  • Integers occurring in the coefficients of the Taylor series of 1/cosh t

    combinatorics, specifically when counting the number of alternating permutations of a set with an even number of elements. The odd-indexed Euler numbers

    Euler number

    Euler_number

  • Figurate number
  • Size of a geometric arrangement of points

    The term figurate number is used by different writers for members of different sets of numbers, generalizing from triangular numbers to different shapes

    Figurate number

    Figurate number

    Figurate_number

  • Square pyramidal number
  • Number of stacked spheres in a pyramid

    In mathematics, a pyramid number, or square pyramidal number, is a natural number that counts the stacked spheres in a pyramid with a square base. The

    Square pyramidal number

    Square pyramidal number

    Square_pyramidal_number

  • Carmichael number
  • Composite number in number theory

    In number theory, a Carmichael number is a composite number ⁠ n {\displaystyle n} ⁠ which in modular arithmetic satisfies the congruence relation: b n

    Carmichael number

    Carmichael number

    Carmichael_number

  • Vampire number
  • Type of composite number with an even number of digits

    recreational mathematics, a vampire number (or true vampire number) is a composite natural number with an even number of digits, that can be factored into

    Vampire number

    Vampire_number

  • Digit sum
  • Sum of a number's digits

    digit sum of a natural number in a given number base is the sum of all its digits. For example, the digit sum of the decimal number 9045 {\displaystyle 9045}

    Digit sum

    Digit_sum

  • Polite number
  • Type of integer in number theory

    In number theory, a polite number is a positive integer that can be written as the sum of two or more consecutive positive integers. A positive integer

    Polite number

    Polite number

    Polite_number

  • Digital root
  • Repeated sum of a number's digits

    The digital root (also repeated digital sum) of a natural number in a given radix is the (single digit) value obtained by an iterative process of summing

    Digital root

    Digital_root

  • Fermat number
  • Positive integer of the form (2^(2^n))+1

    In mathematics, a Fermat number, named after Pierre de Fermat (1601–1665), the first known to have studied them, is a positive integer of the form: F n

    Fermat number

    Fermat_number

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