58058

Appears in sequences

• Number of equilateral triangles formed by triples of points taken from a hexagonal chunk of side n in the hexagonal lattice.at n=13A008893
• Numbers k such that both k and 2*k are balanced numbers (A020492).at n=32A076375
• Numbers n such that sigma(n) = 6*phi(n).at n=14A104900
• Expansion of 1 / (1 - x - x^2 + x^3 - x^5 + x^15 - x^17 - x^18 + x^19 + x^20).at n=31A174650
• a(n) = n*(n + 1)*(n + 2)*(n + 3)*(n + 4)*(n^2 - n + 6)/720.at n=10A256861
• Number of connected (6,2)-chordal bipartite graphs on n nodes.at n=12A280764
• Approximation of the 2-adic integer arctan(2) up to 2^n.at n=16A309751