187254domain: NAppears in sequencesTotal number of line segments between points visible to each other in a square n X n lattice.at n=27A141255Bisection of main diagonal of A115009.at n=13A358297a(n) is the first nonprime k such that the sum over the A389751(n) consecutive nonprimes starting at k equals A389751(n)^3.at n=10A390586