343860domain: NAppears in sequencesNumber of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={-1,2}.at n=23A080004Number of distinct edges among all circles that can be constructed on vertices of an n-sided regular polygon, using only a compass.at n=32A359047