22776

Appears in sequences

• Numbers k that divide phi(k)^2 + sigma(k)^2.at n=33A068484
• Structured hexagonal diamond numbers (vertex structure 5).at n=25A100178
• G.f.: A(x) = F(x*G(x)^4) = F(G(x)-1) where F(x) = G(x/F(x)^2) = 1 + x*F(x)^2 is the g.f. of A000108 (Catalan) and G(x) = F(x*G(x)^2) = 1 + x*G(x)^4 is the g.f. of A002293.at n=6A153397
• Numbers n such that n^2 is a sum of 2 and also of 4 consecutive primes.at n=20A252066
• Number of n X 2 nonnegative integer arrays with upper left 0 and every value within 2 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.at n=24A252814
• Coordination sequence for (2,4,5) tiling of hyperbolic plane.at n=34A265060
• Expansion of Product_{k>=1} (1 + x^(k^2))^2/(1 - x^(k^2))^2.at n=32A279227
• Number of connected subsets of n edges of the rhombic triacontahedron up to the 120 rotations and reflections of the rhombic triacontahedron.at n=9A383983