A025173 The Gegenbauer Polynomial of index n, order 1, evaluated at x=1/3 and multiplied by n*3^n/2.

0, 1, -5, -42, -22, 575, 1677, -3332, -27740, -23859, 259055, 832370, -981714, -10980437, -13342175, 85437240, 319499912, -192522535, -3642631389, -5753449394, 24313788850, 108290637399, -13811840779, -1096315586380, -2152355798868, 6240751807525

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Wikipedia, Gegenbauer Polynomials

Index entries for linear recurrences with constant coefficients, signature (4,-22,36,-81).

Formula

G.f.: ( x-9*x^2 ) / (1-2*x+9*x^2)^2 . - R. J. Mathar, Feb 05 2013

Maple

a:= n-> (<<0|1|0|0>, <0|0|1|0>, <0|0|0|1>, <-81|36|-22|4>>^n. <<0, 1, -5, -42>>)[1, 1]: seq(a(n), n=0..50); # Alois P. Heinz, Feb 05 2013

Mathematica

Table[ n/2 3^n GegenbauerC[ n, 1, 1/3 ], {n, 24} ]

Crossrefs

Sequence in context: A340535 A145008 A216610 * A222474 A327269 A266021

Adjacent sequences: A025170 A025171 A025172 * A025174 A025175 A025176

Keyword

sign

Author

Wouter Meeussen

Status

approved