A329968 a(0) = 1; a(n) = Sum_{k=1..n} |Stirling1(n,k)| * a(n-k).

1, 1, 2, 8, 77, 2329, 302564, 222085736, 1123297137786, 45315713537365706, 16445319538981321524068, 59677257201788875416461684008, 2382127122661172512076372104185900762, 1141042791864963721866517729601372480006639394, 7105297245805890887235402087045369387823693986873653108

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..44

Maple

a:= proc(n) option remember; `if`(n=0, 1,
      add(a(n-j)*abs(Stirling1(n, j)), j=1..n))
    end:
seq(a(n), n=0..14);  # Alois P. Heinz, Feb 25 2025

Mathematica

a[n_] := a[n] = Sum[Abs[StirlingS1[n, k]] a[n - k], {k, 1, n}]; a[0] = 1; Table[a[n], {n, 0, 13}]

Crossrefs

Cf. A008275, A086555, A308444, A329967.

Sequence in context: A193205 A303943 A295345 * A093062 A057984 A215741

Adjacent sequences: A329965 A329966 A329967 * A329969 A329970 A329971

Keyword

nonn,changed

Author

Ilya Gutkovskiy, Nov 26 2019

Status

approved