A155634 7^n + 5^n - 1.

1, 11, 73, 467, 3025, 19931, 133273, 901667, 6155425, 42306731, 292240873, 2026154867, 14085427825, 98109713531, 684326588473, 4778079088067, 33385518460225, 233393453440331, 1632228295176073, 11417968671701267

Offset: 0

Author

Mohammad K. Azarian, Jan 30 2009

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (13,-47,35).

Programs

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 *)

PARI

a(n)=7^n+5^n-1 \\ Charles R Greathouse IV, Dec 22 2011

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]