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A155634
7^n + 5^n - 1.
17
1, 11, 73, 467, 3025, 19931, 133273, 901667, 6155425, 42306731, 292240873, 2026154867, 14085427825, 98109713531, 684326588473, 4778079088067, 33385518460225, 233393453440331, 1632228295176073, 11417968671701267
OFFSET
0,2
FORMULA
G.f.: 1/(1-7*x)+1/(1-5*x)-1/(1-x). E.g.f.: e^(7*x)+e^(5*x)-e^x.
a(n)=12*a(n-1)-35*a(n-2)-24 with a(0)=1, a(1)=11 [From Vincenzo Librandi, Jul 21 2010]
MATHEMATICA
Table[7^n+5^n-1, {n, 0, 30}] (* or *) LinearRecurrence[{13, -47, 35}, {1, 11, 73}, 30] (* Harvey P. Dale, Jun 02 2021 *)
PROG
(PARI) a(n)=7^n+5^n-1 \\ Charles R Greathouse IV, Dec 22 2011
CROSSREFS
Sequence in context: A163775 A092244 A342830 * A335828 A003367 A121784
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Jan 30 2009
STATUS
approved