OFFSET
0,3
COMMENTS
The vincular pattern 23-4-1 requires the 2 and the 3 to be adjacent.
By the trivial Wilf equivalence obtained by reversing the permutations, a(n) is also the number of cyclic patterns of length n that avoid the vincular pattern 32-1-4.
LINKS
Rupert Li, Vincular Pattern Avoidance on Cyclic Permutations, arXiv:2107.12353 [math.CO], 2021.
Toufik Mansour and Mark Shattuck, Enumerating circular permutations avoiding the vincular pattern 23 4 1, arXiv:2111.04211 [math.CO], 2021.
Toufik Mansour and Mark Shattuck, On a question of Li concerning an uncounted class of circular permutations, The Australasian Journal of Combinatorics, volume 83 part 1, 2022, pp. 176-195.
CROSSREFS
KEYWORD
nonn
AUTHOR
Rupert Li, Aug 03 2021
EXTENSIONS
More terms from Vaclav Kotesovec, Nov 09 2021, computed by Toufik Mansour and Mark Shattuck
STATUS
approved