39729927744domain: NAppears in sequencesNumber of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=4.at n=7A321060Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=8.at n=3A321064