A215611 Odd integers n such that 2^n == 2^8 (mod n).

1, 127, 3473, 19313, 30353, 226703, 230777, 345023, 929783, 1790159, 1878073, 2569337, 3441743, 4213511, 8026103, 9770153, 19139183, 24261623, 30652223, 35482433, 38044223, 40642103, 55015793, 65046479, 67411121, 69601193, 119611073

Offset: 1

Author

Max Alekseyev, Aug 17 2012

Keywords

• nonn

Comments

Also, the odd solutions to 2^(n-8) == 1 (mod n). The only even solution is n=8.

For all m, 2^A051447(m)-1 belongs to this sequence.

Links

• Max Alekseyev, Table of n, a(n) for n = 1..859 (all terms below 10^14)

Crossrefs

The odd terms of A015929.

Cf. A051447, A033984, A173572, A215610, A215612, A215613.

Programs

Mathematica

m = 2^8; Join[Select[Range[1, m, 2], Divisible[2^# - m, #] &],
Select[Range[m + 1, 10^6, 2], PowerMod[2, #, #] == m &]] (* Robert Price, Oct 12 2018 *)