Least number m such that 5^m == +- 1 (mod 5n + 1).

Terms

a(0) =1a(1) =5a(2) =4a(3) =3a(4) =2a(5) =3a(6) =6a(7) =10a(8) =11a(9) =16a(10) =6a(11) =15a(12) =10a(13) =5a(14) =9a(15) =27a(16) =21a(17) =12a(18) =8a(19) =25a(20) =26a(21) =36a(22) =14a(23) =55a(24) =3a(25) =65a(26) =16a(27) =23a(28) =36a(29) =75