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Square of triangular matrix A104445, read by rows, where X=A104445 satisfies: SHIFT_LEFT_UP(X) = X^2 - X + I.
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%I #7 Jun 13 2017 01:29:48

%S 1,2,1,3,2,1,5,5,2,1,10,13,7,2,1,25,39,25,9,2,1,78,139,100,41,11,2,1,

%T 296,587,459,205,61,13,2,1,1330,2897,2418,1149,366,85,15,2,1,6935,

%U 16462,14506,7233,2421,595,113,17,2,1,41352,106301,98161,50905,17706,4535,904

%N Square of triangular matrix A104445, read by rows, where X=A104445 satisfies: SHIFT_LEFT_UP(X) = X^2 - X + I.

%C Column 0: T(n,0) = 1 + A091352(n-1) for n>0. Column 1 is A104447. Row sums form A104448.

%F T(n, k) = A104445(n, k) + A104445(n+1, k+1) - I(n, k), where I=identity matrix. T(n, k) = A091351(n-1, k) + A091351(n, k+1) - I(n, k), for n>k>=0.

%e Rows begin:

%e 1;

%e 2,1;

%e 3,2,1;

%e 5,5,2,1;

%e 10,13,7,2,1;

%e 25,39,25,9,2,1;

%e 78,139,100,41,11,2,1;

%e 296,587,459,205,61,13,2,1;

%e 1330,2897,2418,1149,366,85,15,2,1

%e 6935,16462,14506,7233,2421,595,113,17,2,1; ...

%o (PARI) T(n,k)=local(A=Mat(1),B);for(m=1,n,B=A^2-A+A^0; A=matrix(m+1,m+1);for(i=1,m+1, for(j=1,i, if(i<2 || j==i,A[i,j]=1,if(j==1,A[i,j]=1,A[i,j]=B[i-1,j-1]))))); return((A^2)[n+1,k+1])

%Y Cf. A104445, A091351, A091352, A104447, A104448.

%K nonn,tabl

%O 0,2

%A _Paul D. Hanna_, Mar 08 2005