A383878 Number of permutations of [n] with distinct cycle lengths whose GCD is 1.

0, 1, 0, 3, 8, 50, 264, 2394, 15840, 158976, 1490400, 20124720, 181543680, 3213905760, 36459964800, 602127540000, 9045463311360, 187660890063360, 2596164765465600, 64849189355274240, 1037566851245568000, 24684232291242854400, 498833466644833689600

Offset: 0

Author

Alois P. Heinz, May 13 2025

Keywords

• nonn

Examples

			a(3) = 3: (1)(23), (13)(2), (12)(3).
a(4) = 8: (1)(234), (1)(243), (134)(2), (143)(2), (124)(3), (142)(3), (123)(4), (132)(4).
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..450
• Wikipedia, Permutation

Crossrefs

Cf. A079128, A382781.

Programs

Maple

b:= proc(n, i, m) option remember; `if`(i*(i+1)/2 b(n$2, 0):
seq(a(n), n=0..23);