7951296domain: NAppears in sequencesThe number of even permutations p of 1,2,...,n such that -1<=p(i)-i<=2 for i=1,2,...,n.at n=27A268306Number of length-n binary vectors beginning with 0, ending with 1, and avoiding 4 consecutive 0's and 4 consecutive 1's.at n=28A283834