OFFSET
0,2
LINKS
Paolo Xausa, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (13,-44,32).
FORMULA
G.f.: 1/(1-8*x)-1/(1-4*x)+1/(1-x).
E.g.f.: exp(8*x)-exp(4*x)+exp(x).
a(n) = 12*a(n-1)-32*a(n-2)+21 with a(0) = 1, a(1) = 5. - Vincenzo Librandi, Jul 21 2010
MATHEMATICA
Table[8^n - 4^n + 1, {n, 0, 25}] (* Paolo Xausa, Jul 30 2024 *)
PROG
(PARI) a(n)=8^n-4^n+1 \\ Charles R Greathouse IV, Sep 24 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Jan 30 2009
STATUS
approved