This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A015924 #24 Dec 03 2021 11:40:28
%S A015924 1,2,4,6,7,8,12,16,20,24,28,40,44,48,52,60,68,76,80,92,112,116,120,
%T A015924 124,148,154,164,172,188,204,208,212,236,240,244,264,268,280,284,292,
%U A015924 316,332,340,356,364,388,404,412,428,436,452,508,520,524,548,556,596
%N A015924 Positive integers n such that 2^n == 16 (mod n).
%C A015924 Odd terms are given by A033984.
%C A015924 For all m, 2^A128121(m)-1 belongs to this sequence.
%H A015924 T. D. Noe, <a href="/A015924/b015924.txt">Table of n, a(n) for n = 1..1000</a>
%H A015924 OEIS Wiki, <a href="/wiki/2^n mod n">2^n mod n</a>
%t A015924 Select[Range[1000], Mod[2^# - 2^4, #] == 0 &] (* _T. D. Noe_, Aug 17 2012 *)
%t A015924 Join[{1,2,4,6,7,8,12,16},Select[Range[600],PowerMod[2,#,#]==16&]] (* _Harvey P. Dale_, Dec 03 2021 *)
%Y A015924 Contains A050992 as a subsequence.
%Y A015924 Cf. A033984, A173138.
%K A015924 nonn
%O A015924 1,2
%A A015924 _Robert G. Wilson v_
%E A015924 Edited and terms 1,2,4,6,7,8,12,16 prepended by _Max Alekseyev_, Jul 29 2011