((2^m - 1) / p) mod p, where p = prime(n) and m = ord(2,p).

Terms

a(0) =1a(1) =3a(2) =1a(3) =5a(4) =3a(5) =15a(6) =3a(7) =20a(8) =1a(9) =1a(10) =1a(11) =32a(12) =37a(13) =22a(14) =36a(15) =8a(16) =36a(17) =10a(18) =1a(19) =7a(20) =49a(21) =48a(22) =23a(23) =77a(24) =92a(25) =81a(26) =13a(27) =95a(28) =49a(29) =1