104273domain: NAppears in sequencesPositive numbers y such that y^2 is of the form x^2+(x+617)^2 with integer x.at n=10A160176Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-2) - 1, where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.at n=21A293317