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Row sums of triangle A111845, which shifts columns left and up under matrix 4th power.
1

%I #6 Mar 14 2015 10:03:38

%S 1,2,9,97,2689,214017,53130241,43283609601,119521939222529,

%T 1144341237628100609,38638551719263573098497,

%U 4662529388979590206324834305,2032489532637330252763496597356545

%N Row sums of triangle A111845, which shifts columns left and up under matrix 4th power.

%o (PARI) {a(n,q=4)=local(A=Mat(1),B);if(n<0,0, for(m=1,n+1,B=matrix(m,m);for(i=1,m, for(j=1,i, if(j==i,B[i,j]=1,if(j==1,B[i,j]=(A^q)[i-1,1], B[i,j]=(A^q)[i-1,j-1]));));A=B); return(sum(k=0,n,A[n+1,k+1])))}

%Y Cf. A111845 (triangle), A078537 (variant).

%K nonn

%O 0,2

%A _Paul D. Hanna_, Aug 23 2005