A386451 G.f. A(x) satisfies A(x) = 1/(1 - x - x^6*A'''''(x)).
1, 1, 1, 1, 1, 1, 121, 87361, 220324321, 1481019998401, 22395984195495601, 677299352559157967041, 37550830682188851813205921, 3568906049019293501471580099841, 551188987985086896272084982413188201, 132418744847944340085178947237195978556801, 47718683730343729293790168893699493431209021761
Offset: 0
Keywords
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=v[i]+sum(j=0, i-1, sum(k=1, 5, stirling(5, k, 1)*j^k)*v[j+1]*v[i-j])); v;
Formula
a(0) = 1; a(n) = a(n-1) + Sum_{k=0..n-1} (24*k - 50*k^2 + 35*k^3 - 10*k^4 + k^5) * a(k) * a(n-1-k).