A176726 Numerator of a-sequence for Sheffer triangle A060081.

1, 0, -2, 0, -32, 0, -704, 0, -54784, 0, -2610176, 0, -10976325632, 0, -52971659264, 0, -179326416191488, 0, -24309257264168960, 0, -69389116291423404032, 0, -8404514249426618810368, 0, -81520321871322828385550336, 0, -438807077783516207378333696, 0, -690781531822985516802849636352

Offset: 0

Author

Wolfdieter Lang, Jul 14 2010

Keywords

• sign
• easy
• frac

Comments

The denominator sequence is A176727.

For a- and z-sequences for Sheffer triangles see the W. Lang link under A006232.

Examples

			Rationals A176726(n)/A176727(n): [1, 0, -2/3, 0, -32/15, 0, -704/21,0,...].
		

Links

• W. Lang: Rationals A176726/A176727.

Crossrefs

A176728/A176729 z-sequence for triangle A060081.

Programs

Mathematica

max = 29; s = x/Log[Sqrt[(1+x)/(1-x)]] + O[x]^max; CoefficientList[s, x] * Range[0, max-1]! // Numerator (* Jean-François Alcover, Oct 04 2016 *)

Formula

E.g.f. for rational a-sequence A176726/A176727: x/log(sqrt((1+x)/(1- x))).