A330017 a(1) = 1; a(n+1) = Sum_{d|n} binomial(n,d) * a(d).

1, 1, 3, 6, 16, 21, 102, 109, 565, 826, 4913, 4924, 28036, 28049, 378218, 427646, 1841532, 1841549, 29704312, 29704331, 182590131, 194454702, 3660242371, 3660242394, 17058569521, 17059419626, 308650641577, 311298706504, 1436650115240, 1436650115269

Offset

1,3

Links

Table of n, a(n) for n=1..30.

Mathematica

a[n_] := a[n] = Sum[Binomial[n - 1, d] a[d], {d, Divisors[n - 1]}]; a[1] = 1; Table[a[n], {n, 1, 30}]

Crossrefs

Cf. A003238, A056045.

Sequence in context: A329124 A116613 A291803 * A212977 A127935 A144538

Adjacent sequences: A330014 A330015 A330016 * A330018 A330019 A330020

Keyword

nonn

Author

Ilya Gutkovskiy, Nov 27 2019

Status

approved