A127780
A127775 * A002260 as infinite lower triangular matrices.
Original entry on oeis.org
1, 3, 6, 5, 10, 15, 7, 14, 21, 28, 9, 18, 27, 36, 45, 11, 22, 33, 44, 55, 66, 13, 26, 39, 52, 65, 78, 91, 15, 30, 45, 60, 75, 90, 105, 120
Offset: 1
First few rows of the triangle:
1;
3, 6;
5, 10, 15;
7, 14, 21, 28;
9, 18, 27, 36, 45;
11, 22, 33, 44, 55, 66;
...
A128821
Triangle T(n,k), 1<=k<=n, read by rows defined by :T(n,k)=C(n,k)*C(n-1,k-1)+C(n,k-1)*C(n-1,k)where C(n,k)=A007318(n,k) .
Original entry on oeis.org
1, 3, 1, 5, 9, 1, 7, 30, 18, 1, 9, 70, 100, 30, 1, 11, 135, 350, 250, 45, 1, 13, 231, 945, 1225, 525, 63, 1, 15, 364, 2156, 4410, 3430, 980, 84, 1, 17, 540, 4368, 12936, 15876, 8232, 1680, 108, 1, 19, 765, 8100, 32760, 58212, 47628, 17640, 2700, 135, 1
Offset: 1
Triangle begins:
1;
3, 1;
5, 9, 1;
7, 30, 18, 1;
9, 70, 100, 30, 1;
11, 135, 350, 250, 45, 1;
13, 231, 945, 1225, 525, 63, 1;
15, 364, 2156, 4410, 3430, 980, 84, 1 ;...
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