A021894 Expansion of 1/((1-x)(1-4x)(1-7x)(1-12x)).

1, 24, 393, 5536, 72513, 914088, 11282041, 137597232, 1666743345, 20110305592, 242090763369, 2910464426688, 34963222353697, 419822302356936, 5039713424985177, 60489483108391504, 725964257087306769

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (24,-183,496,-336).

Formula

a(n) = (9*12^(n+3) - 44*7^(n+3) + 55*4^(n+3) - 20)/3960. - Yahia Kahloune, Jul 05 2013

a(n) = 24*a(n-1) - 183*a(n-2) + 496*a(n-3) - 336*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 - 12 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 11 2013 *)
LinearRecurrence[{24, -183, 496, -336}, {1, 24, 393, 5536}, 20] (* Harvey P. Dale, Apr 14 2023 *)

Crossrefs

Cf. A019628 (first differences).

Sequence in context: A007752 A145602 A020447 * A021694 A019687 A020341

Adjacent sequences: A021891 A021892 A021893 * A021895 A021896 A021897

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved