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A102920 Triangular matrix, read by rows, equal to the matrix square of A102098. 6

%I #4 Mar 30 2012 18:36:44

%S 1,3,4,36,40,9,1036,1128,189,16,56355,61120,9720,576,25,5045370,

%T 5466320,857466,47040,1375,36,679409158,735847800,114915375,6155008,

%U 163500,2808,49,129195427716,139910204080,21813099606,1158059520,29767000,458136

%N Triangular matrix, read by rows, equal to the matrix square of A102098.

%C Column 0 is A102921. Column 1 is A102922.

%e Rows begin:

%e [1],

%e [3,4],

%e [36,40,9],

%e [1036,1128,189,16],

%e [56355,61120,9720,576,25],

%e [5045370,5466320,857466,47040,1375,36],

%e [679409158,735847800,114915375,6155008,163500,2808,49],...

%o (PARI) {T(n,k)=local(A=matrix(1,1),B);A[1,1]=1; for (m=2,n+1,B=matrix(m,m);for (i=1,m, for (j=1,i, if(j==i,B[i,j]=j,B[i,j]=(A^3)[i-1,j]);));A=B); return((A^2)[n+1,k+1])}

%Y Cf. A102098, A102921, A102922, A102916.

%K nonn,tabl

%O 0,2

%A _Paul D. Hanna_, Jan 21 2005

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