26775

Appears in sequences

• Hexagonal pyramidal numbers, or greengrocer's numbers.at n=34A002412
• Odd hexagonal pyramidal numbers.at n=17A015225
• Number of nonempty subsets of {1,2,...,n} in which exactly 3/5 of the elements are <= (n-2)/3.at n=24A048023
• Number of nonempty subsets of {1,2,...,n} in which exactly 3/5 of the elements are <= (n-3)/3.at n=24A048034
• a(1) = 1, a(n+1) is the sum of a(n) and floor( arithmetic mean of a(1) ... a(n) ).at n=43A065094
• Triangle read by rows, T(n, k) = Sum_{j=0..n} C(n-j, n-k)*E2(n, j), where E2 are the second-order Eulerian numbers A201637, for n >= 0 and 0 <= k <= n.at n=25A112493
• Fifth column of triangle A112493 used for e.g.f.s of Stirling2 diagonals.at n=2A112497
• Natural numbers that can be factored into the product of three positive integers whose minimal sum is achieved in more than one way.at n=27A112536
• Triangle read by rows: T(n,k) is the number of partitions of an n-set having k blocks of size > 1 (0<=k<=floor(n/2)).at n=34A124324
• Records for minima of the positive distance d between the seventh power of a positive integer x and the square of an integer y such that d = x^7 - y^2 (x <> k^2 and y <> k^7).at n=9A179784
• Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k increasing cycles of length >=2 (0<=k<= n/2). A cycle (b(1), b(2), ...) is said to be increasing if, when written with its smallest element in the first position, it satisfies b(1) < b(2) < b(3) < ... .at n=34A186757
• Smallest number having exactly n divisors of the form 8*k + 7.at n=10A188226
• Integers, a, which are the solutions to the equation a^2 + b^3 = c^4, with integers a, b > 0, and indexed off of A242183.at n=30A242184
• Positive integers, c, such that there are more than two solutions to the equation a^2 + b^3 = c^4, with a, b > 0.at n=22A242381
• Numbers k such that 3*R_(k+2) + 5*10^k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=27A257026
• Numbers that are products of two triangular numbers in more than one way.at n=44A264961
• Number of symmetric difference-closed 4-sets consisting of sets consisting of an even number of pairwise disjoint 2-subsets of {1,2,...,n}.at n=9A266503
• Numbers k such that 317*2^k+1 is prime.at n=7A322950
• Odd recursive abundant numbers: odd numbers k such that A333926(k) > 2*k.at n=39A333950
• Positions of records in A188172.at n=9A343137