42484682domain: NAppears in sequencesa(n) = Sum_{k=0..n} binomial(7*n,7*k).at n=4A094211Number of closed walks of length n at a vertex of the cyclic graph on 7 nodes C_7.at n=28A094659a(n) = Sum_{k=0..floor(n/7)} binomial(n,7*k).at n=28A306852a(n) = Sum_{k=0..n} binomial(2*n,7*k).at n=14A387845