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%I #16 Oct 12 2018 14:57:50
%S 1,3,7,15,49,91,133,217,255,259,301,427,469,511,527,553,679,721,763,
%T 889,973,1015,1057,1099,1141,1267,1351,1393,1477,1561,1603,1687,1897,
%U 1939,1981,2107,2149,2191,2317,2359,2443,2569,2611,2653,2779,2863,2947,3031,3073,3199,3241,3409,3493,3661,3787
%N Odd integers n such that 2^n == 2^7 (mod n).
%C Also, integers n such that 2^(n-7) == 1 (mod n).
%C Contains A208155 as a subsequence.
%C For all m, 2^A015922(m)-1 belongs to this sequence.
%H Seiichi Manyama, <a href="/A276969/b276969.txt">Table of n, a(n) for n = 1..10000</a>
%t m = 2^7; Join[Select[Range[1, m, 2], Divisible[2^# - m, #] &],
%t Select[Range[m + 1, 10^3, 2], PowerMod[2, #, #] == m &]] (* _Robert Price_, Oct 12 2018 *)
%o (PARI) is(n)=n%2 && Mod(2,n)^n==128 \\ _Charles R Greathouse IV_, Sep 22 2016
%Y The odd terms of A015927.
%Y Odd integers n such that 2^n == 2^k (mod n): A176997 (k=1), A173572 (k=2), A276967 (k=3), A033984 (k=4), A276968 (k=5), A215610 (k=6), this sequence (k=7), A215611 (k=8), A276970 (k=9), A215612 (k=10), A276971 (k=11), A215613 (k=12).
%Y Cf. A015922, A208155.
%K nonn,easy
%O 1,2
%A _Max Alekseyev_, Sep 22 2016
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