A224287 Number of multiplicity free permutations in S_n, i.e., permutations whose Stanley symmetric function is multiplicity free.

1, 2, 6, 24, 120, 718, 4956, 38180, 319280, 2837959

Offset

1,2

Comments

This family is conjectured to be characterized by a finite set of patterns up to S_11.

Links

Table of n, a(n) for n=1..10.

S. Billey and B. Pawlowski, Permutation Patterns, Stanley symmetric functions and generalized Specht modules, arXiv:1304.7870 [math.CO], 2013.

Crossrefs

Cf. A005802, A223905, A224318.

Sequence in context: A374620 A164872 A226437 * A248838 A364231 A364234

Adjacent sequences: A224284 A224285 A224286 * A224288 A224289 A224290

Keyword

nonn,more

Author

Sara Billey, Apr 04 2013

Status

approved