A112912 Column 1 of triangle A112911.
1, 2, 8, 44, 298, 2358, 21154, 211100, 2313030, 27566654, 354806116, 4903884712, 72444584732, 1139381007880, 19012236634968, 335560664081388, 6247230709277958, 122375974186267566, 2516528486416495240
Offset: 0
Keywords
Programs
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PARI
{a(n)=local(A=Mat(1),B);for(m=2,n+2,B=matrix(m,m);for(i=1,m, for(j=1,i, if(j==i,B[i,j]=1,B[i,j]=-j*(A^-1)[i-j,1]);));A=B);return((A^-1)[n+2,2])}
Formula
a(n) = Sum_{k=0..n-1} (n-k+1)*A088716(k)*a(n-k-1) for n>0 with a(0)=1.