A346414 Number of labeled totally ordered commutative semigroups.

1, 1, 4, 20, 114, 710, 4726, 33157, 243048, 1850817, 14590692

Offset

0,3

Links

Table of n, a(n) for n=0..10.

Petr Gajdoš and Martin Kuřil, Ordered semigroups of size at most 7 and linearly ordered semigroups of size at most 10, Semigroup Forum, 89 (2014), 639-663.

Crossrefs

Cf. A023815.

Sequence in context: A287512 A367237 A211248 * A028475 A128327 A320615

Adjacent sequences: A346411 A346412 A346413 * A346415 A346416 A346417

Keyword

nonn,hard,more

Author

Peter Jipsen, Jul 15 2021

Status

approved