A083302 a(n) = (4*9^n + (-1)^n)/5.

1, 7, 65, 583, 5249, 47239, 425153, 3826375, 34437377, 309936391, 2789427521, 25104847687, 225943629185, 2033492662663, 18301433963969, 164712905675719, 1482416151081473, 13341745359733255, 120075708237599297

Offset: 0

Author

Paul Barry, Apr 24 2003

Keywords

• easy
• nonn

Comments

Binomial transform of A083301.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..300
• Index entries for linear recurrences with constant coefficients, signature (8,9).

Programs

Magma

[(4*9^n+(-1)^n)/5: n in [0..25]]; // Vincenzo Librandi, Jun 29 2011

PARI

a(n)=4*9^n\/5 \\ Charles R Greathouse IV, Jun 29 2011

Formula

G.f.: (1-x)/((1-*9x)(1+x)).

E.g.f.: (4*exp(9*x) + exp(-x))/5.