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,-167,385)
FORMULA
a(n) = 5^(n+2)/12+11^(n+2)/24-7^(n+2)/8. - R. J. Mathar, Mar 15 2011
a(0)=1, a(1)=23, a(2)=362; for n>2, a(n) = 23*a(n-1) -167*a(n-2) +385*a(n-3). - Vincenzo Librandi, Jul 03 2013
a(n) = 18*a(n-1) -77*a(n-2) +5^n. - Vincenzo Librandi, Jul 03 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - 5 x) (1 - 7 x) (1 - 11 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 03 2013 *)
PROG
(PARI) Vec(1/((1-5*x)*(1-7*x)*(1-11*x))+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012
(Magma) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-5*x)*(1-7*x)*(1-11*x)))); /* or */ I:=[1, 23, 362]; [n le 3 select I[n] else 23*Self(n-1)-167*Self(n-2)+385*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 03 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved