4115479104domain: NAppears in sequencesa(n) = sqrt(Product_{1<=j,k<=n} (4*sin((2*j-1)*Pi/(2*n))^2 + 4*sin((2*k-1)*Pi/n)^2)).at n=6A341535a(n) = sqrt( Product_{j=1..n} Product_{k=1..6} (4*sin((2*j-1)*Pi/(2*n))^2 + 4*sin((2*k-1)*Pi/6)^2) ).at n=5A341545