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 A104138 #15 May 31 2014 19:13:01 %S A104138 2,3,7,7,23,23,89,89,113,113,113,113,113,113,523,523,523,523,887,887, %T A104138 1129,1129,1327,1327,1327,1327,1327,1327,1327,1327,1327,1327,1327, %U A104138 1327,9551,9551,15683,15683,15683,15683,15683,15683,15683,15683,19609 %N A104138 Smallest prime followed by n or more composites. %C A104138 Except for a(1), records occur at even values of n, and each term appears an even number of times consecutively. (Proof. A maximal run of composites must begin and end at even numbers.) - _Jonathan Sondow_, May 31 2014 %H A104138 Charles R Greathouse IV, <a href="/A104138/b104138.txt">Table of n, a(n) for n = 0..1000</a> %F A104138 Record prime A002386(n+1) appears A053695(n-1) times, for n>1. %F A104138 a(n) = A030296(n) - 1, for n > 0. - _Jonathan Sondow_, May 31 2014 %e A104138 a(10)=113 because it is the first prime occurring before primes 199,211,293,317,467,509,... all followed by at least ten successive composites. %Y A104138 Cf. A002386, A005250, A030296, A053695. %K A104138 nonn %O A104138 0,1 %A A104138 _Lekraj Beedassy_, Mar 07 2005 %E A104138 a(34) corrected by _Charles R Greathouse IV_, Aug 09 2011