A113378 Triangle, read by rows, equal to the matrix cube of A113370.
1, 3, 1, 15, 12, 1, 136, 168, 21, 1, 1998, 3190, 483, 30, 1, 41973, 80136, 13615, 960, 39, 1, 1166263, 2553162, 469476, 35785, 1599, 48, 1, 40747561, 99579994, 19419225, 1562220, 74074, 2400, 57, 1, 1726907675, 4624245724, 944233801, 79072620
Offset: 0
Examples
Triangle A113370^3 begins: 1; 3,1; 15,12,1; 136,168,21,1; 1998,3190,483,30,1; 41973,80136,13615,960,39,1; 1166263,2553162,469476,35785,1599,48,1; 40747561,99579994,19419225,1562220,74074,2400,57,1; 1726907675,4624245724,944233801,79072620,3908034,132856,3363,66,1;
Programs
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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);(A^3)[n+1,k+1]