309120

Appears in sequences

• Total number of nodes in all trees with n nodes.at n=15A055543
• One of a family of sequences that interpolates between the Bell numbers and the factorials.at n=8A068201
• Numbers k such that 1*k + 1, 3*k + 1, 9*k + 1, 27*k + 1, 81*k + 1 are all primes.at n=15A112042
• Number of 6-cycles in the n X n rook graph.at n=7A288960
• Expansion of e.g.f. 1/(1 + x * log(1-2*x)).at n=7A367883
• Expansion of e.g.f. 1/(1 + (log(1 - x^2))/x).at n=8A375798