Indices k such that 22 plus the k-th triangular number is a perfect square.

Terms

a(0) =2a(1) =12a(2) =27a(3) =77a(4) =162a(5) =452a(6) =947a(7) =2637a(8) =5522a(9) =15372a(10) =32187a(11) =89597a(12) =187602a(13) =522212a(14) =1093427a(15) =3043677a(16) =6372962a(17) =17739852a(18) =37144347a(19) =103395437a(20) =216493122a(21) =602632772a(22) =1261814387a(23) =3512401197a(24) =7354393202a(25) =20471774412a(26) =42864544827a(27) =119318245277a(28) =249832875762