A155633 a(n) = 6^n + 5^n - 1.

1, 10, 60, 340, 1920, 10900, 62280, 358060, 2070240, 12030820, 70231800, 411625180, 2420922960, 14281397140, 84467679720, 500702562700, 2973697798080, 17689598897860, 105374653934040, 628433226338620, 3751525871703600, 22413787798580980, 134005889633282760, 801651152008680940

Offset

0,2

Links

Paolo Xausa, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (12,-41,30).

Formula

G.f.: 1/(1-6*x)+1/(1-5*x)-1/(1-x). E.g.f.: e^(6*x)+e^(5*x)-e^x.

a(n)=11*a(n-1)-30*a(n-2)-20 with a(0)=1, a(1)=10 - Vincenzo Librandi, Jul 21 2010

Mathematica

A155633[n_] := 6^n + 5^n - 1; Array[A155633, 25, 0] (* Paolo Xausa, Apr 03 2026 *)

Prog

(PARI) a(n)=6^n+5^n-1^n \\ Charles R Greathouse IV, Jun 11 2015

Crossrefs

Cf. A155596, A155597, A155598, A155599, A155600, A155601, A155622, A155623, A155624, A155625, A155626, A155627, A155628, A155629, A155630, A155631.

Sequence in context: A292489 A083585 A250575 * A368525 A002493 A054364

Adjacent sequences: A155630 A155631 A155632 * A155634 A155635 A155636

Keyword

nonn,easy

Author

Mohammad K. Azarian, Jan 30 2009

Extensions

More terms from Paolo Xausa, Apr 03 2026

Status

approved