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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 Cf. A048143, A198085, A261006, A304912, A304981, A304982, A304983, A304984, A304985, A304986, A304997. Sequence in context: A122081 A007140 A161936 * A260887 A127850 A324147 Adjacent sequences:  A304980 A304981 A304982 * A304984 A304985 A304986 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 September 20 08:08 EDT 2019. Contains 327214 sequences. (Running on oeis4.)