21086

Appears in sequences

• Number of unrooted achiral trees with n nodes.at n=38A003244
• Decimal part of a(n)^(1/5) starts with a 'nine digits' anagram.at n=8A034280
• Coefficients of derivatives of MacMahon polynomials (A060187): p(x,n)=2^n*(1 - x)^(1 + n)*LerchPhi[x, -n, 1/2]; p'(x,n)=(d/dx)p{x,n).at n=16A142707
• Number of union-closed partitions of weight n.at n=43A225973
• Expansion of f(-x^3, -x^5) * f(x^3, x^13) / (f(-x, -x^2) * f(-x^8, -x^16)) in powers of x where f(, ) is Ramanujan's general theta function.at n=44A258939
• Number of partitions of n whose greatest part is a multiple of 3.at n=43A363045
• Number of rooted ordered trees with node weights summing to n, where the root has weight 0, non-root node weights are in {1,2,3}, and no nodes have the same weight as their parent node.at n=11A382096