Number of integer solutions to x^2 + y^2 <= n excluding (0,0).

Terms

a(0) =0a(1) =4a(2) =8a(3) =8a(4) =12a(5) =20a(6) =20a(7) =20a(8) =24a(9) =28a(10) =36a(11) =36a(12) =36a(13) =44a(14) =44a(15) =44a(16) =48a(17) =56a(18) =60a(19) =60a(20) =68a(21) =68a(22) =68a(23) =68a(24) =68a(25) =80a(26) =88a(27) =88a(28) =88a(29) =96