Numbers k such that 28 plus the k-th triangular number is a perfect square.

Terms

a(0) =6a(1) =8a(2) =47a(3) =57a(4) =278a(5) =336a(6) =1623a(7) =1961a(8) =9462a(9) =11432a(10) =55151a(11) =66633a(12) =321446a(13) =388368a(14) =1873527a(15) =2263577a(16) =10919718a(17) =13193096a(18) =63644783a(19) =76895001a(20) =370948982a(21) =448176912a(22) =2162049111a(23) =2612166473a(24) =12601345686a(25) =15224821928a(26) =73446025007a(27) =88736765097a(28) =428074804358a(29) =517195768656