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A144942 Expansion of x^2*(3*x^3+145*x^2-507*x-25) / ((x-1)*(x^2-34*x+1)*(x^2+34*x+1)). 1
0, 25, 532, 29237, 614312, 33739857, 708915900, 38935766125, 818088334672, 44931840368777, 944073229295972, 51851304849802917, 1089459688519217400, 59836360864832197825, 1257235536477947584012, 69051108586711506487517, 1450848719635862992732832 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also the index of the first of two consecutive pentagonal numbers whose sum is also a pentagonal number. - Colin Barker, Dec 22 2014

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..200

Index entries for linear recurrences with constant coefficients, signature (1,1154,-1154,-1,1).

MATHEMATICA

CoefficientList[Series[x (3 x^3 + 145 x^2 - 507 x - 25)/((x - 1) (x^2 - 34 x + 1) (x^2 + 34 x + 1)), {x, 0, 20}], x] (* Vincenzo Librandi, Oct 20 2014 *)

PROG

(PARI) concat(0, Vec(x^2*(3*x^3+145*x^2-507*x-25)/((x-1)*(x^2-34*x+1)*(x^2+34*x+1)) + O(x^20))) \\ Colin Barker, Oct 20 2014

CROSSREFS

Cf. A133301, A144796, A144797.

Sequence in context: A028341 A282689 A282874 * A122140 A083191 A226299

Adjacent sequences:  A144939 A144940 A144941 * A144943 A144944 A144945

KEYWORD

easy,nonn

AUTHOR

Richard Choulet, Sep 26 2008

EXTENSIONS

a(6) corrected, and more terms from Colin Barker, Oct 20 2014

Edited, name changed by Colin Barker, Oct 20 2014

STATUS

approved

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Last modified October 22 05:29 EDT 2019. Contains 328315 sequences. (Running on oeis4.)