Number of positive integer solutions to the Diophantine equation x + y + 2z = n^2.

Terms

a(0) =0a(1) =1a(2) =12a(3) =49a(4) =132a(5) =289a(6) =552a(7) =961a(8) =1560a(9) =2401a(10) =3540a(11) =5041a(12) =6972a(13) =9409a(14) =12432a(15) =16129a(16) =20592a(17) =25921a(18) =32220a(19) =39601a(20) =48180a(21) =58081a(22) =69432a(23) =82369a(24) =97032a(25) =113569a(26) =132132a(27) =152881a(28) =175980a(29) =201601