A021754 Expansion of 1/((1-x)(1-4x)(1-5x)(1-7x)).

1, 17, 190, 1770, 14931, 118587, 905920, 6742340, 49288261, 355826757, 2546230050, 18106416510, 128181315991, 904540692527, 6368500164580, 44764509392280, 314282333570121, 2204653080603897, 15456046918261510, 108310071701877650, 758760684298882651

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (17,-99,223,-140).

Formula

a(n) = (2*7^(n+3)-9*5^(n+3)+8*4^(n+3)-1)/72. [Yahia Kahloune, May 08 2013]

Maple

A021754:=n->(2*7^(n+3)-9*5^(n+3)+8*4^(n+3)-1)/72: seq(A021754(n), n=0..30); # Wesley Ivan Hurt, Apr 18 2017

Mathematica

CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 5 x) (1 - 7 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 11 2013 *)
LinearRecurrence[{17, -99, 223, -140}, {1, 17, 190, 1770}, 30] (* Harvey P. Dale, Apr 14 2022 *)

Prog

(PARI) x='x+O('x^66); Vec(1/((1-x)*(1-4*x)*(1-5*x)*(1-7*x)) ) \\ Joerg Arndt, May 08 2013

Crossrefs

Sequence in context: A115234 A197370 A211848 * A141993 A025467 A322122

Adjacent sequences: A021751 A021752 A021753 * A021755 A021756 A021757

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved