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A113387 Triangle, read by rows, equal to the matrix cube of A113381.

%I A113387 #5 Jun 13 2017 23:29:54
%S A113387 1,6,1,48,15,1,605,255,24,1,11196,5630,624,33,1,280440,159210,19484,
%T A113387 1155,42,1,8981460,5584635,731664,46541,1848,51,1,353283128,236051661,
%U A113387 32532732,2173248,91175,2703,60,1,16567072675,11741443007,1683566556
%N A113387 Triangle, read by rows, equal to the matrix cube of A113381.
%F A113387 Column k of A113381^3 = column 0 of A113389^(3*k+2) for k>=0.
%e A113387 Triangle A113381^3 begins:
%e A113387 1;
%e A113387 6,1;
%e A113387 48,15,1;
%e A113387 605,255,24,1;
%e A113387 11196,5630,624,33,1;
%e A113387 280440,159210,19484,1155,42,1;
%e A113387 8981460,5584635,731664,46541,1848,51,1;
%e A113387 353283128,236051661,32532732,2173248,91175,2703,60,1;
%e A113387 16567072675,11741443007,1683566556,116647443,5086116,157760,3720,69,1;
%o A113387 (PARI) T(n,k)=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,k+1]
%Y A113387 Cf. A113381, A113388 (column 0), A113389.
%K A113387 nonn,tabl
%O A113387 0,2
%A A113387 _Paul D. Hanna_, Nov 14 2005