A136232 Triangle, read by rows, equal to the matrix 4th power of triangle A136220.
1, 4, 1, 24, 8, 1, 198, 76, 12, 1, 2116, 888, 156, 16, 1, 28052, 12542, 2350, 264, 20, 1, 446560, 209506, 41034, 4864, 400, 24, 1, 8325700, 4058806, 821562, 100988, 8710, 564, 28, 1, 178284892, 89706276, 18631332, 2352116, 209440, 14168, 756, 32, 1
Offset: 0
Examples
This triangle P^4 begins: 1, 4, 1; 24, 8, 1; 198, 76, 12, 1; 2116, 888, 156, 16, 1; 28052, 12542, 2350, 264, 20, 1; 446560, 209506, 41034, 4864, 400, 24, 1; 8325700, 4058806, 821562, 100988, 8710, 564, 28, 1; 178284892, 89706276, 18631332, 2352116, 209440, 14168, 756, 32, 1; ... where column k = column 1 of U^(k+1); triangle U = A136228 begins: 1; 1, 1; 3, 4, 1; 15, 24, 7, 1; 108, 198, 63, 10, 1; 1036, 2116, 714, 120, 13, 1; 12569, 28052, 9884, 1725, 195, 16, 1; ... where column k of U = column 0 of P^(3k+1) and triangle P = A136220 begins: 1; 1, 1; 3, 2, 1; 15, 10, 3, 1; 108, 75, 21, 4, 1; 1036, 753, 208, 36, 5, 1; 12569, 9534, 2637, 442, 55, 6, 1; ...
Programs
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PARI
{T(n,k)=local(P=Mat(1),U,PShR);if(n>0,for(i=0,n, PShR=matrix(#P,#P, r,c, if(r>=c,if(r==c,1,if(c==1,0,P[r-1,c-1]))));U=P*PShR^2; U=matrix(#P+1, #P+1, r,c, if(r>=c, if(r<#P+1,U[r,c], if(c==1,(P^3)[ #P,1],(P^(3*c-1))[r-c+1,1])))); P=matrix(#U, #U, r,c, if(r>=c, if(r<#R,P[r,c], (U^c)[r-c+1,1])))));(P^4)[n+1,k+1]}
Formula
Column k of this triangle = column 1 of U^(k+1) where U = A136228.