Nonsquares mod 72.

Terms

a(0) =2a(1) =3a(2) =5a(3) =6a(4) =7a(5) =8a(6) =10a(7) =11a(8) =12a(9) =13a(10) =14a(11) =15a(12) =17a(13) =18a(14) =19a(15) =20a(16) =21a(17) =22a(18) =23a(19) =24a(20) =26a(21) =27a(22) =29a(23) =30a(24) =31a(25) =32a(26) =33a(27) =34a(28) =35a(29) =37