Number of permutations p of [2n] such that the up-down signature of 0,p has nonnegative partial sums with a maximal value of n.

A266947

Number of permutations p of [2n] such that the up-down signature of 0,p has nonnegative partial sums with a maximal value of n.

Terms

    a(0) =1a(1) =1a(2) =11a(3) =130a(4) =4734a(5) =127538a(6) =11174035a(7) =554432537a(8) =92953037066

External references