A309504 - OEIS

%I #17 Jul 21 2020 02:26:40

%S 1,1,2,4,10,24,68,188,586,1722,5492,16924

%N Number of cyclic permutations of length n avoiding the pattern 123.

%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.

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

%Y Cf. A309505, A309506, A309508.

%K nonn,more

%O 1,3

%A _Miklos Bona_, Aug 05 2019