A083315 a(n) = (2*5^n-(4^n-2^n))/2.

1, 4, 19, 97, 505, 2629, 13609, 69997, 357985, 1822309, 9241849, 46731997, 235754065, 1187152789, 5969306089, 29980723597, 150440439745, 754349584069, 3780337658329, 18936047636797, 94817676351025, 474638135996149

Offset: 0

Author

Paul Barry, Apr 24 2003

Keywords

• easy
• nonn

Comments

Binomial transform of A083314.

Links

• Index entries for linear recurrences with constant coefficients, signature (11,-38,40)

Crossrefs

Cf. A083314, A083316.

Formula

G.f.: (1-7*x+13*x^2)/((1-2*x)*(1-4*x)*(1-5*x)).

E.g.f.: (2*exp(5*x)-exp(4*x)+exp(2*x))/2.

a(n) = 11*a(n-1) - 38*a(n-2) + 40*a(n-3). - Wesley Ivan Hurt, Dec 31 2023