267276

Appears in sequences

• G.f. satisfies A(x) = 1 + x*(2*A(x)^2 + A(x)^3).at n=6A219535
• The number of partitions of [n] with exactly 3 blocks without peaks.at n=15A289693
• Square array T(n,k), n>=0, k>=0, read by antidiagonals, where T(0,k) = 1 and T(n,k) = (1/n) * Sum_{j=1..n} 3^j * binomial(n,j) * binomial(k*n,j-1) for n > 0.at n=42A336575