0,2

(PARI) {a(n)=local(A=matrix(1, 1), B); A[1, 1]=1; for(m=2, n+2, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=j, if(j==1, B[i, j]=(A^2)[i-1, 1], B[i, j]=(A^2)[i-1, j])); )); A=B); return(sum(k=0, n, if(k==0, A[n+1, k+1], A[n+1, k]/k^2)))}

Cf. A106210.

Sequence in context: A094664 A001858 A000366 this_sequence A014058 A119602 A121752

Adjacent sequences: A106208 A106209 A106210 this_sequence A106212 A106213 A106214

nonn

Paul D. Hanna (pauldhanna(AT)juno.com), May 01 2005