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 A128003 #32 Aug 05 2020 15:46:19 %S A128003 13,71,181,251,463,521,7321,36473,48157,87421,168527,249341 %N A128003 Numbers n such that (37^n - 1)/36 is prime. %C A128003 7321 is a term found by Richard Fischer in 2004. - _Alexander Adamchuk_, Feb 11 2007 %C A128003 No other terms less than 100000. - _Robert Price_, Mar 18 2012 %H A128003 H. Dubner, <a href="http://dx.doi.org/10.1090/S0025-5718-1993-1185243-9">Generalized repunit primes</a>, Math. Comp., 61 (1993), 927-930. %H A128003 H. Lifchitz, <a href="http://www.primenumbers.net/Henri/us/MersFermus.htm">Mersenne and Fermat primes field</a> %H A128003 <a href="/index/Pri#primepop">Index to primes in various ranges</a>, form ((k+1)^n-1)/k %t A128003 Select[Prime[Range[100]], PrimeQ[(37^#-1)/36]&] %o A128003 (PARI) is(n)=ispseudoprime((37^n-1)/36) \\ _Charles R Greathouse IV_, Feb 17 2017 %K A128003 hard,more,nonn %O A128003 1,1 %A A128003 _Alexander Adamchuk_, Feb 11 2007 %E A128003 a(7) from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008 %E A128003 a(8)-a(10) from _Robert Price_, Mar 18 2012 %E A128003 a(11) from _Paul Bourdelais_, Aug 05 2019 %E A128003 a(12) from _Paul Bourdelais_, Aug 04 2020