11082241domain: NAppears in sequencesa(n) = A000931(n)^2.at n=35A133037Number of subsets S of {1,2,3,...,n} with the property that if x is a member of S then at least one of x-2 and x+2 is also a member of S.at n=29A172020Number of n X 2 binary arrays without the pattern 0 1 0 diagonally, vertically or horizontally.at n=13A188501