OFFSET
0,1
COMMENTS
Primes of this sequence are in A196940.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (3,-2).
FORMULA
a(n) = 15*2^n - 1.
From Philippe Deléham, Feb 17 2014: (Start)
a(n) = 2*a(n-1) + 1.
a(n) = 3*a(n-2) - 2*a(n-2).
a(n) = A110286(n) - 1. (End)
From Elmo R. Oliveira, Sep 14 2024: (Start)
G.f.: (14 - 13*x)/((1 - x)*(1 - 2*x)).
E.g.f.: exp(x)*(15*exp(x) - 1). (End)
PROG
(Magma) [15*2^n -1 : n in [0..50]];
(PARI) a(n)=15<<n-1 \\ Charles R Greathouse IV, Oct 08 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Brad Clardy, Oct 07 2011
STATUS
approved