Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=9.

A321065

Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=9.

Terms

    a(0) =23136128a(1) =873274112a(2) =43316046592

External references