Table T(n,k) in which n-th row lists prime factors of 2^n - 1 (n >= 2), with repetition.

Terms

a(0) =3a(1) =7a(2) =3a(3) =5a(4) =31a(5) =3a(6) =3a(7) =7a(8) =127a(9) =3a(10) =5a(11) =17a(12) =7a(13) =73a(14) =3a(15) =11a(16) =31a(17) =23a(18) =89a(19) =3a(20) =3a(21) =5a(22) =7a(23) =13a(24) =8191a(25) =3a(26) =43a(27) =127a(28) =7a(29) =31