Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=5.

A321061

Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=5.

Terms

    a(0) =88a(1) =952a(2) =17008a(3) =438496a(4) =15214848a(5) =678914816a(6) =37727416576

External references