855119462400domain: NAppears in sequencesNumber of permutations p of (1,2,3,...,n) such that 1*(-1)^p(1)+2*(-1)^p(2)+3*(-1)^p(3)+...+n*(-1)^p(n)=0.at n=16A073410Number of left-right-balanced permutations of {1, 2, ..., n}.at n=15A250035