Number of alternating permutations on 2n+1 letters that avoid a certain pattern of length 4 (see Lewis, 2012, Appendix, for precise definition).
A217799
Number of alternating permutations on 2n+1 letters that avoid a certain pattern of length 4 (see Lewis, 2012, Appendix, for precise definition).
Terms
- a(0) =1a(1) =2a(2) =16a(3) =168a(4) =2112a(5) =30030a(6) =466752a(7) =7759752a(8) =135980416
External references
- oeis: A217799