A023952 Expansion of 1/((1-x)(1-6x)(1-7x)(1-11x)).

1, 25, 416, 5822, 74319, 898779, 10511446, 120335968, 1358681621, 15202492877, 169098946380, 1873624439778, 20707233183547, 228476788273759, 2518219270791458, 27735798399148292, 305344872665615937

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (25,-209,647,-462).

Formula

a(0)=1, a(1)=25, a(2)=416, a(3)=5822, a(n)=25*a(n-1)-209*a(n-2)+ 647*a(n-3)- 462*a(n-4) [Harvey P. Dale, Mar 24 2012]

a(n) = (3*11^(n+3) - 25*7^(n+3) + 24*6^(n+3) - 2)/600. [Yahia Kahloune, Jun 29 2013]

Mathematica

CoefficientList[Series[1 / ((1 - x) (1 - 6 x) (1 - 7 x) (1 - 11 x)), {x, 0, 30}], x] (* or *) LinearRecurrence[{25, -209, 647, -462}, {1, 25, 416, 5822}, 30] (* Harvey P. Dale, Mar 24 2012 *)

Prog

(Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-6*x)*(1-7*x)*(1-11*x)))); /* or */ I:=[1, 25, 416, 5822]; [n le 4 select I[n] else 25*Self(n-1)-209*Self(n-2)+647*Self(n-3)-462*Self(n-4): n in [1..25]]; // Vincenzo Librandi, Jul 13 2013

Crossrefs

Sequence in context: A028037 A102072 A022845 * A025991 A022628 A020838

Adjacent sequences: A023949 A023950 A023951 * A023953 A023954 A023955

Keyword

nonn,easy

Author

N. J. A. Sloane.

Status

approved