OFFSET
0,3
COMMENTS
Suggested by A190173.
LINKS
Bruno Berselli, Table of n, a(n) for n = 0..500
Index entries for linear recurrences with constant coefficients, signature (9,-20,8,5,-1).
FORMULA
G.f.: x^2*(2-x)/((1-x)*(1-6*x+x^2)*(1-2*x-x^2)). [Bruno Berselli, Jun 20 2012]
a(n) = 9*a(n-1) -20*a(n-2) +8*a(n-3) +5*a(n-4) -a(n-5). - Vincenzo Librandi, Jun 20 2012
MATHEMATICA
LinearRecurrence[{9, -20, 8, 5, -1}, {0, 0, 2, 17, 113}, 30] (* Vincenzo Librandi, Jun 20 2012 *)
PROG
(Magma) I:=[0, 0, 2, 17, 113]; [n le 5 select I[n] else 9*Self(n-1)-20*Self(n-2)+8*Self(n-3)+5*Self(n-4)-Self(n-5): n in [1..30]]; // Vincenzo Librandi, Jun 20 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jun 20 2012
STATUS
approved