Number of permutations of length 3n with descent set {3, 6, ...} that avoid a certain pattern of length 4 or 5 (see Lewis, 2012, Appendix, for precise definition).
A217829
Number of permutations of length 3n with descent set {3, 6, ...} that avoid a certain pattern of length 4 or 5 (see Lewis, 2012, Appendix, for precise definition).
Terms
- a(0) =1a(1) =19a(2) =1134a(3) =115515a(4) =16254118a(5) =2848701388
External references
- oeis: A217829