A114150 Triangle, read by rows, given by the product R^2*Q^-1 = Q^3*P^-2 using triangular matrices P=A113370, Q=A113381, R=A113389.
1, 4, 1, 28, 7, 1, 326, 91, 10, 1, 5702, 1722, 190, 13, 1, 136724, 43764, 4945, 325, 16, 1, 4226334, 1415799, 163705, 10751, 496, 19, 1, 161385532, 56096733, 6617605, 437723, 19896, 703, 22, 1
Offset: 0
Examples
Triangle R^2*Q^-1 = Q^3*P^-2 begins: 1; 4,1; 28,7,1; 326,91,10,1; 5702,1722,190,13,1; 136724,43764,4945,325,16,1; 4226334,1415799,163705,10751,496,19,1; ... Compare to P (A113370): 1; 1,1; 1,4,1; 1,28,7,1; 1,326,91,10,1; 1,5702,1722,190,13,1; ... Thus R^2*Q^-1 = Q^3*P^-2 equals P shift left one column.
Crossrefs
Programs
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PARI
T(n,k)=local(P,Q,R,W);P=Mat(1);for(m=2,n+1,W=matrix(m,m); for(i=1,m, for(j=1,i,if(i<3 || j==i || j>m-1,W[i,j]=1,if(j==1, W[i,1]=1,W[i,j]=(P^(3*j-2))[i-j+1,1]));));P=W); Q=matrix(#P,#P,r,c,if(r>=c,(P^(3*c-1))[r-c+1,1])); R=matrix(#P,#P,r,c,if(r>=c,(P^(3*c))[r-c+1,1])); (R^2*Q^-1)[n+1,k+1]
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