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.

A091029 Signed array used for numerators of generating functions of the column sequences of array A090452.

Original entry on oeis.org

1, 3, -2, 2, 6, -9, 3, 15, 0, -24, 18, -4, 5, 69, -75, -20, 60, -30, 5, 63, 217, -462, 225, 80, -120, 45, -6, 14, 462, 300, -1848, 1785, -525, -210, 210, -63, 7, 252, 2460, -1809, -4932, 8428, -5208, 1050, 448, -336, 84, -8, 42, 2556, 9747, -18775, -2655, 28296, -28182, 12726, -1890, -840, 504, -108, 9
Offset: 2

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Author

Wolfdieter Lang, Dec 23 2003

Keywords

Comments

The row polynomials P(m,x) := sum(a(m,k)*x^k,k=0..kmax(m)),m>=2, where kmax(m) := floor(3*m/2)-3=A032766(m-2)=[0,1,3,4,6,7,9,10,...], appear in the numerator of the g.f.s of the columns of A090452.
The sequence of the lengths of the rows is [1,2,4,5,7,8,10,11,13,14,...]=A001651(m-2)= floor((3*m-4)/2).

Examples

			[1]; [3,-2]; [2,6,-9,3]; [15,0,-24,18,-4]; ...
P(3,x)=3-2*x; P(5,x)=15-24*x^2+18*x^3-4*x^4.
		

Formula

a(m, k)=[x^k]P(m, x), with P(m, x) := ((1-x)^(2*m-3))*G(m, x)/x^ceiling(m/2) and the G(m, x) satisfy the hypergeometric differential difference eq. given in A090452.