50969640960domain: NAppears in sequencesNumber of permutations p of {1,2,...,n} such that p(j) + p(n+1-j) != n+1 for all j.at n=14A155518a(0)=1, a(1)=0, a(n) = 4*n*(n-1)*(a(n-1) + 2*(n-1)*a(n-2)).at n=7A189849Number of permutations p of [n] satisfying |p(i+7) - p(i)| <> 7 for all 1 <= i <= n-7.at n=14A360384