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A304983 Number of unlabeled clutters (connected antichains) spanning n vertices with singleton edges allowed. 8
1, 1, 3, 14, 118, 2916, 819473 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
FORMULA
Inverse Euler transform of A304997. - Andrew Howroyd, Aug 14 2019
EXAMPLE
Non-isomorphic representatives of the a(3) = 14 clutters:
{{1,2,3}}
{{1,3},{2,3}}
{{3},{1,2,3}}
{{1,2},{1,3},{2,3}}
{{3},{1,2},{2,3}}
{{3},{1,3},{2,3}}
{{2},{3},{1,2,3}}
{{1},{2},{3},{1,2,3}}
{{2},{3},{1,2},{1,3}}
{{3},{1,2},{1,3},{2,3}}
{{2},{3},{1,3},{2,3}}
{{1},{2},{3},{1,3},{2,3}}
{{2},{3},{1,2},{1,3},{2,3}}
{{1},{2},{3},{1,2},{1,3},{2,3}}
CROSSREFS
Sequence in context: A122081 A007140 A161936 * A349013 A260887 A127850
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, May 23 2018
EXTENSIONS
a(5)-a(6) from Andrew Howroyd, Aug 14 2019
STATUS
approved

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Last modified February 28 16:26 EST 2024. Contains 370400 sequences. (Running on oeis4.)