|
COMMENTS
|
Equivalent definitions:
(1) Permutations that have the form (a_1, a_2, ..., a_k, b_1, b_2, ..., b_(n - k)), where the subsequences (a_1, a_2, ..., a_k) and (b_1, b_2, ..., b_(n - k)) avoid the permutation pattern 2143 and a_i < b_j for all i, j.
(2) Permutations that avoid the nine permutation patterns 24153, 25143, 31524, 31542, 32514, 32541, 42153, 52143, and 214365.
|