Number of permutations p of [n] such that the up-down signature of p has nonnegative partial sums with a maximal value <= 2.

A262126

Number of permutations p of [n] such that the up-down signature of p has nonnegative partial sums with a maximal value <= 2.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =3a(4) =8a(5) =40a(6) =162a(7) =1134a(8) =6128a(9) =55152a(10) =372560a(11) =4098160a(12) =33220512a(13) =431866656a(14) =4084265360a(15) =61263980400a(16) =662157708032

External references