%I #11 Oct 09 2018 15:16:16

%S 1,31,18631,55831,92329,3014633,3556559,6429121,9664591,12158831,

%T 33554431,34844431,566740481,644903881,727815241,842608801,2207017049,

%U 2208171881,2445644207,8694918511,9031128791,18738146881,27345981361,35476604081

%N Odd integers n such that 2^n == 2^6 (mod n).

%C Also, the odd solutions to 2^(n-6) == 1 (mod n). The only even solution is n=6.

%C For all m, 2^A033981(m)-1 belongs to this sequence.

%H Max Alekseyev, <a href="/A215610/b215610.txt">Table of n, a(n) for n = 1..102</a> (all terms below 10^14)

%t m = 64; Join[Select[Range[1, m, 2], Divisible[2^# - m, #] &],

%t Select[Range[m + 1, 10^6, 2], PowerMod[2, #, #] == m &]] (* _Robert Price_, Oct 08 2018 *)

%Y The odd terms of A015926.

%Y Cf. A173572, A033984, A215611, A215612, A215613

%K nonn

%O 1,2

%A _Max Alekseyev_, Aug 17 2012