A373455 Number of interval posets of permutations of size n, considered up to isomorphism.

1, 1, 2, 6, 15, 43, 124, 379, 1172, 3730, 12023, 39388, 130377, 436066, 1470271, 4994083, 17069343, 58669677, 202648664, 703064353, 2448871526, 8560428736, 30021944259, 105602286616, 372469127865, 1317027839250, 4667702488376, 16578315095909

Offset

1,3

Comments

See Remark 21 in [Bouvel-Cioni-Izart].

References

Bridget E. Tenner. Interval Posets of Permutations. Order, 39(3):523-536, 2022.

Links

Table of n, a(n) for n=1..28.

Mathilde Bouvel, Lapo Cioni, and Benjamin Izart, The interval posets of permutations seen from the decomposition tree perspective, arXiv:2110.10000 [math.CO], 2021-2024.

Bridget E. Tenner, Interval Posets for Permutations, arXiv:2007.06142 [math.CO], 2020-2021.

Formula

Asymptotic behavior of a(n) is c*n^(-3/2)*r^n with c approximately 0.1964 and r approximately 3.7545. See M. Bouvel, L. Cioni, B. Izart (Remark 21).

Crossrefs

For the same posets but not considered up to isomorphism, see A348479.

For the same posets which are in addition trees, see A373456.

Sequence in context: A338861 A340726 A303833 * A148438 A148439 A151515

Adjacent sequences: A373452 A373453 A373454 * A373456 A373457 A373458

Keyword

nonn

Author

Mathilde Bouvel, Jun 06 2024

Status

approved