3689595domain: NAppears in sequencesa(n) = 7*binomial(8*n+7,n)/(8*n+7).at n=6A234466a(n) = binomial(n^2 + n - 1, n) / (n^2 + n - 1).at n=6A351501a(0) = 1; a(n) = Sum_{k=0..floor((n-1)/7)} a(7*k) * a(n-1-7*k).at n=48A386396