A136535 A128064 * A001263.

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, 645, 141, 7, 1, 77, 833, 2695, 3185, 1421, 217, 8, 1, 100, 1456, 6664, 11956, 9016, 2800, 316, 9, 1, 126, 2376, 14616, 37044, 42336, 22176, 5076, 441, 10

Offset

1,3

Comments

Row sums give A076540.

Links

Table of n, a(n) for n=1..55.

Example

First few rows of the triangle are:
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, 645, 141, 7;
...

Prog

(PARI) T4(n, k) = sum(j=k, n, binomial(n, j)*binomial(j, k)*(-1)^(j-k)*(j+1));
T3(n, k) = binomial(n, k)*binomial(n-1, k-1) - binomial(n, k-1)*binomial(n-1, k);
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

Crossrefs

Cf. A001263, A128064, A076540.

Sequence in context: A295734 A197328 A352247 * A320579 A091370 A125697

Adjacent sequences: A136532 A136533 A136534 * A136536 A136537 A136538

Keyword

nonn,tabl

Author

Gary W. Adamson, Jan 04 2008

Extensions

a(18) corrected by Georg Fischer, Oct 10 2021

Status

approved