OFFSET
1,3
COMMENTS
Isomorphism is up to permutation of the elements of the n-set.
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..50
EXAMPLE
The a(3)=6 sets with permutations shown in cycle notation are:
{(1)(2)(3), (1)(23), (12)(3)},
{(1)(2)(3), (1)(23), (123)},
{(1)(2)(3), (123), (132)},
{(1)(23), (12)(3), (123)},
{(1)(23), (12)(3), (13)(2)},
{(1)(23), (123), (132)}.
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, May 03 2023
STATUS
approved