A309505 - OEIS

A309505

Number of cyclic permutations of length n that avoid the pattern 132 (equivalently, 213).

%I #16 Jul 21 2020 02:26:51

%S 1,1,2,4,10,24,68,182,544,1574,4888,14864

%N Number of cyclic permutations of length n that avoid the pattern 132 (equivalently, 213).

%H Miklos Bona, Michael Cory, <a href="http://arxiv.org/abs/1805.05196">Cyclic Permutations Avoiding Pairs of Patterns of Length Three</a>, arXiv:1805.05196 [math.CO], 2018.

%H Brice Huang, <a href="https://arxiv.org/abs/1808.08462">An Upper Bound on the Number of (132,213)-Avoiding Cyclic Permutations</a>, arXiv:1808.08462 [math.CO], 2018-2019.

%e For n=3, there are two such permutations, 231 and 312.

%Y Cf. A309504, A309506, A309508.

%K nonn,more

%O 1,3

%A _Miklos Bona_, Aug 05 2019