277495domain: NAppears in sequencesNumber of distinct lines through the origin in the n-dimensional lattice of side length 5.at n=7A090021Number of distinct lines through the origin in 7-dimensional cube of side length n.at n=5A090029a(n) = Sum_{1 <= x_1, x_2, ... , x_n <= n} n/gcd(x_1, x_2, ... , x_n, n).at n=5A372969