Smallest x such that sigma(x) == n-1 (mod n).

Terms

a(0) =1a(1) =1a(2) =7a(3) =2a(4) =3a(5) =2401a(6) =5a(7) =4a(8) =7a(9) =18a(10) =21a(11) =9604a(12) =6a(13) =9a(14) =13a(15) =8a(16) =44a(17) =21609a(18) =10a(19) =18a(20) =19a(21) =289a(22) =36a(23) =9604a(24) =14a(25) =162a(26) =57a(27) =72a(28) =12a(29) =2614689