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Column 1 of triangular matrix A102101, which shifts upward to exclude the main diagonal under matrix fourth power.
1

%I #4 Mar 30 2012 18:36:44

%S 0,2,16,1040,196080,82196224,65585046960,89664824687968,

%T 194650170795350624,633421180929983545024,2953697281799409438455088,

%U 19035190329068182887341039344,164578521474330559730154886587328

%N Column 1 of triangular matrix A102101, which shifts upward to exclude the main diagonal under matrix fourth power.

%o (PARI) {a(n)=local(A=matrix(2,2),B);A[1,1]=1; for(m=2,n+1,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^4)[i-1,1], B[i,j]=(A^4)[i-1,j]));));A=B); return(A[n+1,2])}

%Y Cf. A102101.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Dec 29 2004