Squares mod 31.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =5a(5) =7a(6) =8a(7) =9a(8) =10a(9) =14a(10) =16a(11) =18a(12) =19a(13) =20a(14) =25a(15) =28