OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (22,-152,320).
FORMULA
a(n)= 2*4^n/3 -8^(n+1)+25*10^n/3 . - R. J. Mathar, Nov 11 2012
a(0)=1, a(1)=22, a(2)=332; for n>2, a(n) = 22*a(n-1) -152*a(n-2) +320*a(n-3). - Vincenzo Librandi, Jul 03 2013
a(n) = 18*a(n-1) -80*a(n-2) +4^n. - Vincenzo Librandi, Jul 03 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - 4 x) (1 - 8 x) (1 - 10 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 03 2013 *)
LinearRecurrence[{22, -152, 320}, {1, 22, 332}, 20] (* Harvey P. Dale, Aug 28 2013 *)
PROG
(Magma) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-4*x)*(1-8*x)*(1-10*x)))); // Vincenzo Librandi, Jul 03 2013
(Magma) I:=[1, 22, 332]; [n le 3 select I[n] else 22*Self(n-1)-152*Self(n-2)+320*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 03 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved