Numbers having exactly four representations by the quadratic form x^2+xy+y^2 with 0<=x<=y.

Terms

a(0) =1729a(1) =2821a(2) =3367a(3) =3913a(4) =4123a(5) =4459a(6) =4921a(7) =5187a(8) =5551a(9) =5719a(10) =6097a(11) =6517a(12) =6643a(13) =6916a(14) =7189a(15) =7657a(16) =8029a(17) =8113a(18) =8463a(19) =8827a(20) =8911a(21) =9139a(22) =9331a(23) =9373a(24) =9709a(25) =9919a(26) =10101a(27) =10507a(28) =10621a(29) =10633