Triangular numbers representable as triangular(x)*triangular(y)+1.

Terms

a(0) =1a(1) =10a(2) =91a(3) =136a(4) =946a(5) =1711a(6) =1891a(7) =5671a(8) =8911a(9) =10585a(10) =11026a(11) =11935a(12) =13861a(13) =19306a(14) =21736a(15) =26335a(16) =32131a(17) =36856a(18) =44551a(19) =49141a(20) =65341a(21) =107416a(22) =138601a(23) =239086a(24) =305371a(25) =351541a(26) =366796a(27) =459361a(28) =849556a(29) =873181