OFFSET
0,3
COMMENTS
Only the non-singleton edges are required to form an antichain.
LINKS
FORMULA
For n > 1, a(n) = A048143(n) * 2^n.
EXAMPLE
The a(2) = 4 clutters:
{{1,2}}
{{1},{1,2}}
{{2},{1,2}}
{{1},{2},{1,2}}
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 23 2018
STATUS
approved