a(1) = 1; a(n+1) is the smallest k > a(n) such that 2^k == 2^a(n) (mod a(n)).

Terms

a(0) =1a(1) =2a(2) =3a(3) =5a(4) =9a(5) =15a(6) =19a(7) =37a(8) =73a(9) =82a(10) =102a(11) =110a(12) =130a(13) =142a(14) =177a(15) =235a(16) =327a(17) =363a(18) =473a(19) =543a(20) =723a(21) =747a(22) =993a(23) =1023a(24) =1033a(25) =1291a(26) =2581a(27) =2889a(28) =3843a(29) =3903