A036781 a(n) = n + Sum_{k=0..n} k!.

1, 3, 6, 13, 38, 159, 880, 5921, 46242, 409123, 4037924, 43954725, 522956326, 6749977127, 93928268328, 1401602636329, 22324392524330, 378011820620331, 6780385526348332, 128425485935180333, 2561327494111820334, 53652269665821260335, 1177652997443428940336

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..400

Maple

a:= proc(n) option remember; `if`(n=0, 1, a(n-1)+1+n!) end:
seq(a(n), n=0..30);  # Alois P. Heinz, Jan 05 2015

Mathematica

Module[{nn=30, f}, f=Accumulate[Range[0, nn]!]; Table[n+f[[n]], {n, nn}]]-1 (* Harvey P. Dale, Nov 04 2020 *)
Module[{nn=30, f}, f=Accumulate[Range[0, nn]!]; Total/@Thread[{f, Range[0, nn]}]] (* Harvey P. Dale, Jan 31 2023 *)

Crossrefs

A003422[ n ] + n.

Cf. A007489.

Sequence in context: A053564 A264236 A216999 * A370208 A084816 A055738

Adjacent sequences: A036778 A036779 A036780 * A036782 A036783 A036784

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved