A360887 G.f. satisfies A(x) = 1 + x * (1 + x)^2 * A(x * (1 + x)).
1, 1, 3, 7, 22, 76, 290, 1225, 5616, 27758, 147050, 829926, 4966258, 31382572, 208676004, 1455540594, 10620614461, 80869622604, 641177678068, 5282866462839, 45152445030267, 399673570426188, 3658433105500600, 34582526451125235, 337165886689229224
Offset: 0
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 0..577
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=0, i-1, binomial(i+1-j, j)*v[i-j])); v;
Formula
a(0) = 1; a(n) = Sum_{k=0..n-1} binomial(n+1-k,k) * a(n-1-k).