Number of solutions to x^2 + x*y + y^2 <= n, excluding (0,0), divided by 6.

Terms

a(0) =0a(1) =1a(2) =1a(3) =2a(4) =3a(5) =3a(6) =3a(7) =5a(8) =5a(9) =6a(10) =6a(11) =6a(12) =7a(13) =9a(14) =9a(15) =9a(16) =10a(17) =10a(18) =10a(19) =12a(20) =12a(21) =14a(22) =14a(23) =14a(24) =14a(25) =15a(26) =15a(27) =16a(28) =18a(29) =18