A083305 a(n) = (4*(n+10)^n+n^n)/5.

1, 9, 116, 1763, 30784, 608125, 13431104, 328435647, 8819323904, 258227642321, 8194000000000, 280279062767899, 10285785324929024, 403289664570492357, 16830798499899981824, 745145638470458984375, 34890683668357841158144, 1723120618512823480401433, 89530853568169585920966656

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..300

Formula

a(n) ~ (4*exp(10-50/(2*n))+1) * n^n / 5. - Amiram Eldar, Feb 09 2026

Mathematica

A083305[n_] := If[n == 0, 1, (4*(n + 10)^n + n^n)/5];
Array[A083305, 20, 0] (* Paolo Xausa, Oct 27 2025 *)

Prog

(Magma) [(4*(n+10)^n+n^n)/5: n in [0..25]]; // Vincenzo Librandi, Jun 29 2011
(PARI) a(n)= (4*(n+10)^n+n^n)/5 \\ Charles R Greathouse IV, Jun 29 2011

Crossrefs

Cf. A000312, A083304, A083306.

Sequence in context: A188976 A180913 A341964 * A222146 A253655 A092913

Adjacent sequences: A083302 A083303 A083304 * A083306 A083307 A083308

Keyword

easy,nonn

Author

Paul Barry, Apr 24 2003

Status

approved