Positions of even numbers in A004431 (sums of 2 distinct nonzero squares).

Terms

a(0) =2a(1) =5a(2) =7a(3) =9a(4) =11a(5) =14a(6) =15a(7) =17a(8) =20a(9) =22a(10) =23a(11) =24a(12) =27a(13) =29a(14) =31a(15) =32a(16) =35a(17) =37a(18) =39a(19) =40a(20) =43a(21) =44a(22) =48a(23) =49a(24) =51a(25) =53a(26) =54a(27) =58a(28) =60a(29) =61