11299968domain: NAppears in sequencesa(n) = Pell(n)*A000118(n) for n>=1 with a(0)=1, where A000118(n) is the number of ways of writing n as a sum of 4 squares.at n=16A209443Solutions y to the negative Pell equation y^2 = 72*x^2 - 288 with x,y >= 0.at n=8A281234