91144

Appears in sequences

• Fine's sequence (or Fine numbers): number of relations of valence >= 1 on an n-set; also number of ordered rooted trees with n nodes having root of even degree.at n=13A000957
• Generalized Catalan numbers C(-1; n).at n=13A064310
• Numbers n such that 4*10^n + 2*R_n - 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=11A102984
• Expansion of (1-2*x-sqrt(1-4*x))/(x^2 * (1+2*x+sqrt(1-4*x))).at n=10A104629
• A bisection of A000957.at n=6A138414