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%I #14 Oct 11 2021 04:19:38

%S 1,1,2,1,7,3,1,15,21,4,1,26,76,46,5,1,40,200,250,85,6,1,57,435,925,

%T 645,141,7,1,77,833,2695,3185,1421,217,8,1,100,1456,6664,11956,9016,

%U 2800,316,9,1,126,2376,14616,37044,42336,22176,5076,441,10

%N A128064 * A001263.

%C Row sums give A076540.

%e First few rows of the triangle are:

%e 1;

%e 1, 2;

%e 1, 7, 3;

%e 1, 15, 21, 4;

%e 1, 26, 76, 46, 5;

%e 1, 40, 200, 250, 85, 6;

%e 1, 57, 435, 925, 645, 141, 7;

%e ...

%o (PARI) T4(n,k) = sum(j=k, n, binomial(n,j)*binomial(j,k)*(-1)^(j-k)*(j+1));

%o T3(n,k) = binomial(n, k)*binomial(n-1, k-1) - binomial(n, k-1)*binomial(n-1, k);

%o N=10; matrix(N, N, n, k, T4(n-1,k-1))*matrix(N, N,n,k,T3(n,k)) \\ _Michel Marcus_, Oct 11 2021

%Y Cf. A001263, A128064, A076540.

%K nonn,tabl

%O 1,3

%A _Gary W. Adamson_, Jan 04 2008

%E a(18) corrected by _Georg Fischer_, Oct 10 2021