cp's OEIS Frontend

A121415 Column 3 of triangle A121412, in which row n of T=A121412 equals row (n-1) of T^(n+1) with an appended '1'.

%I A121415 #3 Mar 30 2012 18:36:58
%S A121415 1,1,6,63,924,17226,387567,10182744,305379129,10280074116,
%T A121415 383492465902,15692864353299,698622377024472,33604795914668178,
%U A121415 1736477536255603281,95918139377302294980,5639487915973132301793,351611645300506492405623
%N A121415 Column 3 of triangle A121412, in which row n of T=A121412 equals row (n-1) of T^(n+1) with an appended '1'.
%C A121415 Also equals column 5 of triangle A101479.
%o A121415 (PARI) {a(n)=local(A=Mat(1), B); for(m=1, n+4, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, B[i, j]=(A^i)[i-1, j]); )); A=B); return((A^1)[n+4, 4])}
%Y A121415 Cf. A121412 (triangle); other columns: A101483, A121413, A121414; A101479 (triangle).
%K A121415 nonn
%O A121415 0,3
%A A121415 _Paul D. Hanna_, Aug 22 2006