OFFSET
0,5
LINKS
Wikipedia, Partition of a set
EXAMPLE
a(0) = 1: () the empty partition.
a(3) = 1: 13|2.
a(4) = 3: 124|3, 13|2|4, 14|2|3.
a(5) = 13: 1235|4, 124|35, 124|3|5, 125|34, 125|3|4, 13|245, 13|2|45, 13|2|4|5, 145|2|3, 14|2|35, 14|2|3|5, 15|2|34, 15|2|3|4.
a(6) = 50: 12346|5, 1235|46, 1235|4|6, 1236|45, ..., 15|2|3|4|6, 16|2|35|4, 16|2|3|45, 16|2|3|4|5.
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 17 2023
STATUS
approved