A345136 a(1) = 1; a(n) = Sum_{d|n, d < n} binomial(n,d) * a(d).

1, 2, 3, 16, 5, 96, 7, 1184, 261, 1360, 11, 97428, 13, 24220, 16395, 15267456, 17, 14474736, 19, 251423600, 817971, 7760236, 23, 264344406312, 265675, 135208476, 1223270127, 971632668664, 29, 2584070688810, 31, 9176980861031424, 2128920321, 39671306896, 48694835

Offset

1,2

Links

Table of n, a(n) for n=1..35.

Mathematica

a[1] = 1; a[n_] := a[n] = Sum[If[d < n, Binomial[n, d] a[d], 0], {d, Divisors[n]}]; Table[a[n], {n, 1, 35}]

Crossrefs

Cf. A008578 (fixed points), A056045, A074206, A330017.

Sequence in context: A176029 A218323 A369893 * A128537 A266265 A259209

Adjacent sequences: A345133 A345134 A345135 * A345137 A345138 A345139

Keyword

nonn

Author

Ilya Gutkovskiy, Jun 09 2021

Status

approved