cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A206735 Triangle T(n,k), read by rows, given by (0, 2, -1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, -1/2, 1/2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938.

Original entry on oeis.org

1, 0, 1, 0, 2, 1, 0, 3, 3, 1, 0, 4, 6, 4, 1, 0, 5, 10, 10, 5, 1, 0, 6, 15, 20, 15, 6, 1, 0, 7, 21, 35, 35, 21, 7, 1, 0, 8, 28, 56, 70, 56, 28, 8, 1, 0, 9, 36, 84, 126, 126, 84, 36, 9, 1, 0, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1, 0, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1
Offset: 0

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Author

Philippe Deléham, Feb 11 2012

Keywords

Comments

A103452*A007318 as infinite lower triangular matrices.
Essentially the same as A199011.

Examples

			Triangle begins :
1
0, 1
0, 2, 1
0, 3, 3, 1
0, 4, 6, 4, 1
0, 5, 10, 10, 5, 1
0, 6, 15, 20, 15, 6, 1
0, 7, 21, 35, 35, 21, 7, 1
0, 8, 28, 56, 70, 56, 28, 8, 1
0, 9, 36, 84, 126, 126, 84, 36, 9, 1
0, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1
0, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1
		

Crossrefs

Cf. A007318, A000071 (antidiagonal sums).

Formula

T(n,k) = A007318(n,k) - A073424(n,k).
Sum_{k, 0<=k<=n} T(n,k)*x^k = (1+x)^n - 1 + 0^n.
T(n,0) = 0^n = A000007(n), T(n,k) = binomial(n,k) for k>0.
G.f.: (1-2*x+(1+y)*x^2)/(1-2x+(1+y)*x^2-y*x).
Sum{k, 0<=k<=n} T(n,k)^x = A000027(n+1), A000225(n), A030662(n), A096191(n), A096192(n) for x = 0, 1, 2, 3, 4 respectively.