A307346 - OEIS

A307346

Number of uniquely sorted permutations of [2n+1] that avoid the patterns 231 and 4123.

%I #12 Apr 24 2019 11:47:49

%S 1,1,3,10,36,138,553,2288,9699,41908

%N Number of uniquely sorted permutations of [2n+1] that avoid the patterns 231 and 4123.

%H C. Defant, <a href="https://arxiv.org/abs/1904.02627">Catalan intervals and uniquely sorted permutations</a>, arXiv:1904.02627 [math.CO], 2019.

%e The 3 uniquely sorted permutations of [7] that avoid 231 and 4123 are 2164357, 2143657, and 4321567.

%Y Cf. A180874.

%K nonn,more

%O 0,3

%A _Colin Defant_, Apr 03 2019