login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

a(n) = n! + 3^n.
2

%I #20 Aug 29 2022 20:42:30

%S 2,4,11,33,105,363,1449,7227,46881,382563,3687849,40093947,479533041,

%T 6228615123,87183074169,1307688716907,20922832934721,355687557236163,

%U 6402374093148489,121645101571093467,2432902011663424401,51090942182169793203,1124000727808988739609

%N a(n) = n! + 3^n.

%F a(n) = n! + 3^n.

%F a(n) = A000142(n) + A000244(n).

%F E.g.f.: 1/(1-x) + exp(3*x). - _Alois P. Heinz_, Aug 29 2022

%p A249945:=n->3^n+n!: seq(A249945(n), n=0..25); # _Wesley Ivan Hurt_, Nov 14 2014

%t Table[3^n + n!, {n, 20}] (* _Alonso del Arte_, Nov 09 2014 *)

%o (PARI) vector(10,n,3^n + n!) \\ _Derek Orr_, Nov 14 2014

%o (Magma) [3^n+Factorial(n) : n in [0..25]]; // _Wesley Ivan Hurt_, Nov 14 2014

%Y Cf. A000142, A000244, A007611.

%K nonn,easy

%O 0,1

%A _Max Alweiss_, Nov 08 2014