OFFSET
0,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (5,9).
FORMULA
a(n) = 5*a(n-1) + 9*a(n-2).
MATHEMATICA
a[n_]:=(MatrixPower[{{1, 3}, {1, -6}}, n].{{1}, {1}})[[2, 1]]; Table[Abs[a[n]], {n, -1, 40}] (* Vladimir Joseph Stephan Orlovsky, Feb 19 2010 *)
LinearRecurrence[{5, 9}, {0, 1}, 30] (* Vincenzo Librandi, Nov 13 2012 *)
PROG
(Sage) [lucas_number1(n, 5, -9) for n in range(0, 21)]# Zerinvary Lajos, Apr 24 2009
(Magma) [n le 2 select n-1 else 5*Self(n-1) + 9*Self(n-2): n in [1..30]]; // Vincenzo Librandi, Nov 13 2012
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-5*x-9*x^2))) \\ G. C. Greubel, Jan 24 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved