Least number m such that 4^m == +- 1 (mod 4n + 1).

Terms

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