43316046592domain: NAppears in sequencesNumber of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=3.at n=8A321059Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=9.at n=2A321065