OFFSET
1,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..300
Index entries for linear recurrences with constant coefficients, signature (1,16,-16).
FORMULA
G.f.: (1+x-8*x^2)/(2*(-1+x)*(-1+4*x)*(1+4*x)). - Vaclav Kotesovec, Nov 28 2012
a(n) = (4 + (-4)^n + 5*4^n)/20. - Gerry Martens, May 26 2024
PROG
(PARI) a(n)=(4+(-4)^n+5*4^n)/20 \\ Charles R Greathouse IV, Jul 08 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Artur Jasinski, Jan 27 2006
EXTENSIONS
Edited with better definition and offset corrected by Omar E. Pol, Jan 08 2009
STATUS
approved