A019752 G.f.: 1/((1-4x)(1-11x)(1-12x)).

1, 27, 505, 8115, 120241, 1695387, 23126185, 308127555, 4034342881, 52117311147, 666165944665, 8442335850195, 106239836635921, 1329127977509307, 16546285315207945, 205119670292296035, 2533642759410327361, 31197987005034321867, 383112856942345668025

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..900

Index entries for linear recurrences with constant coefficients, signature (27,-224,528).

Formula

From Vincenzo Librandi, Oct 09 2011: (Start)

a(n) = (7*12^(n+2)+4^(n+2)-8*11^(n+2))/56.

a(n) = 23*a(n-1) - 132*a(n-2) + 4^n.

a(n) = 27*a(n-1) - 224*a(n-2) + 528*a(n-3), n>=3. (End)

Mathematica

CoefficientList[Series[1/((1-4x)(1-11x)(1-12x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{27, -224, 528}, {1, 27, 505}, 30] (* Harvey P. Dale, Jul 16 2017 *)

Prog

(Magma) [(7*12^(n+2)+4^(n+2)-8*11^(n+2))/56 : n in [0..20]]; // Vincenzo Librandi, Oct 09 2011
(PARI) Vec(1/((1-4*x)*(1-11*x)*(1-12*x)) + O(x^30)) \\ Michel Marcus, Dec 27 2014

Crossrefs

Sequence in context: A021994 A020568 A021734 * A001709 A016887 A110896

Adjacent sequences: A019749 A019750 A019751 * A019753 A019754 A019755

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

More terms from Michel Marcus, Dec 27 2014

Status

approved