OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..100
Index entries for linear recurrences with constant coefficients, signature (3,4).
FORMULA
G.f.: x*(3-5*x)/(1-3*x-4*x^2). - Bruno Berselli, May 24 2011
MATHEMATICA
LinearRecurrence[{3, 4}, {3, 4}, 40]
PROG
(Maxima) a[1]:3$ a[2]:4$ a[n]:=3*a[n-1]+4*a[n-2]$ makelist(a[n], n, 1, 25); /* Bruno Berselli, May 24 2011 */
(PARI) a(n)=7<<(2*n)\/20-2*(-1)^n \\ Charles R Greathouse IV, Jul 15 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Harvey P. Dale, Apr 26 2011
STATUS
approved