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 A057612 #8 Jan 17 2019 18:33:43 %S A057612 3,7,31,127,8191,131071,524287,8388607 %N A057612 Numbers that are both Mersenne numbers (A001348) and lucky numbers (A000959). %C A057612 a(9) > 2^31 - 1 (by exhaustive search). - _Jon Maiga_, Jan 17 2019 %Y A057612 Cf. A000959, A001348. %K A057612 nonn,more %O A057612 1,1 %A A057612 _Naohiro Nomoto_, Oct 09 2000 %E A057612 More terms from Mark Weston (mweston(AT)uvic.ca), Oct 10 2001