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%I #5 Jun 13 2017 23:30:49
%S 1,6,48,605,11196,280440,8981460,353283128,16567072675,905357065354,
%T 56632746126107,3997082539456084,314584709388906568,
%U 27340439653453247728,2602372304420672868499,269388182085308601450047
%N Column 0 of triangle A113387, also equals column 0 of A113389^2.
%F A113387 equals the matrix cube of A113381, which has the property: column k of A113381^3 = column 0 of A113389^(3*k+2) for k>=0.
%o (PARI) a(n)=local(A,B);A=Mat(1);for(m=2,n+1,B=matrix(m,m); for(i=1,m, for(j=1,i,if(i<3 || j==i || j>m-1,B[i,j]=1,if(j==1, B[i,1]=1,B[i,j]=(A^(3*j-2))[i-j+1,1]));));A=B); (matrix(#A,#A,r,c,if(r>=c,(A^(3*c-1))[r-c+1,1]))^3)[n+1,1]
%Y Cf. A113381, A113387, A113389.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Nov 14 2005
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