A367830 E.g.f. A(x) satisfies A(x) = (1 + (exp(x) - 1) * A(2*x)) / (1 - x).
1, 2, 13, 208, 7817, 681626, 136872113, 62739300968, 64993463748977, 150619722938940622, 773428868899900772345, 8724654696222415759129388, 214574098061440421518595200025, 11429824974654804201081062775335234, 1311103770238649103823410558613476172193
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]=i*v[i]+sum(j=1, i, 2^(i-j)*binomial(i, j)*v[i-j+1])); v;
Formula
a(0) = 1; a(n) = n * a(n-1) + Sum_{k=1..n} 2^(n-k) * binomial(n,k) * a(n-k).