Position of n^2 in A003136.

Terms

a(0) =1a(1) =2a(2) =4a(3) =6a(4) =9a(5) =12a(6) =16a(7) =21a(8) =26a(9) =32a(10) =37a(11) =44a(12) =50a(13) =57a(14) =66a(15) =74a(16) =83a(17) =91a(18) =101a(19) =111a(20) =123a(21) =134a(22) =145a(23) =157a(24) =168a(25) =182a(26) =195a(27) =209a(28) =223a(29) =237