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 A128125 #31 Jun 13 2021 03:22:26 %S A128125 1,2,3,10,1010,61610,469730,2037190,3820821,9227438,21728810,24372562, %T A128125 207034456857,1957657325241,2002159320610,35169368880130, %U A128125 36496347203230,116800477091426 %N A128125 Numbers k such that 2^k == 14 (mod k). %C A128125 No other terms below 10^15. Some larger terms: 279283702428813463, 3075304070192893442, 21894426987819404424310, 4616079845508388554313022889, 82759461944940747300611642693066719359651817521, 446*(2^445-7)/1061319625781480182060453906975 (107 digits). - _Max Alekseyev_, Oct 03 2016 %H A128125 Joe K. Crump, <a href="http://web.archive.org/web/20070614175509/http://www.immortaltheory.com/NumberTheory/2nmodn.htm">2^n mod n</a> %t A128125 For[n=1, n<= 10^6, n++, If[PowerMod[2,n,n] == Mod[14,n], Print[n]]] (* _Stefan Steinerberger_, May 05 2007 *) %t A128125 m = 14; Join[Select[Range[m], Divisible[2^# - m, #] &], %t A128125 Select[Range[m + 1, 10^6], PowerMod[2, #, #] == m &]] (* _Robert Price_, Oct 08 2018 *) %Y A128125 Cf. A015910, A036236, A050259 (numbers k such that 2^k == 3 (mod k)), A033981, A051447, A033982, A051446, A033983, A128121, A128122, A128123, A128124, A128126. %K A128125 hard,more,nonn %O A128125 1,2 %A A128125 _Alexander Adamchuk_, Feb 15 2007 %E A128125 1, 2, 3 and 10 added by _N. J. A. Sloane_, Apr 23 2007 %E A128125 More terms from _Stefan Steinerberger_, May 05 2007 %E A128125 a(13) from _Max Alekseyev_, May 15 2011 %E A128125 a(14), a(16), a(17) from _Max Alekseyev_, Dec 16 2013 %E A128125 a(15), a(18) from _Max Alekseyev_, Oct 03 2016