A021884 Expansion of 1/((1-x)(1-4x)(1-7x)(1-11x)).

1, 23, 358, 4758, 58419, 686541, 7864936, 88727036, 991573957, 11016698979, 121950785034, 1346833901634, 14852822151415, 163644677778137, 1801937252261452, 19834231783445352, 218267009404507593

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (23,-171,457,-308).

Formula

a(n) = (9*11^(n+3)-35*7^(n+3)+40*4^(n+3)-14)/2520. - Yahia Kahloune, May 24 2013

a(n) = 23*a(n-1) - 171*a(n-2) + 457*a(n-3) - 308*a(n-4) for n > 3. - Chai Wah Wu, Feb 03 2021

Mathematica

CoefficientList[Series[1 / ((1 - x) (1 - 4 x) (1 - 7 x) (1 - 11 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 11 2013 *)
LinearRecurrence[{23, -171, 457, -308}, {1, 23, 358, 4758}, 20] (* Harvey P. Dale, Apr 02 2022 *)

Crossrefs

Cf. A019623 (first differences).

Sequence in context: A025946 A118115 A020572 * A101792 A020346 A025964

Adjacent sequences: A021881 A021882 A021883 * A021885 A021886 A021887

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved