62594domain: NAppears in sequencesNumber of minimum sized maximal subsets of {1..n} such that every pair of distinct elements has a different difference.at n=44A382396a(n) = Sum_{k=0..floor(n/6)} (7*k+1) * binomial(2*n-5*k+1,n-6*k)/(2*n-5*k+1).at n=11A390481