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 A122091 #7 May 13 2013 01:54:09 %S A122091 199,317,509,523,619,839,887,1069,1129,1259,1327,1409,1459,1499,1637, %T A122091 1669,1709,1759,1789,1847,1889,1913,1951,2039,2069,2099,2179,2311, %U A122091 2357,2399,2477,2503,2557,2579,2819,2939,2971,3049,3089,3137,3169,3229,3259 %N A122091 Numbers appearing in A122072 at least twice. %C A122091 Necessary condition: p is followed by a prime gap of at least 12. Sufficient condition: p is followed by a prime gap of at least 20. [_Charles R Greathouse IV_, Feb 26 2012] %H A122091 Charles R Greathouse IV, <a href="/A122091/b122091.txt">Table of n, a(n) for n = 1..10000</a> %F A122091 a(n) ~ n log n since this sequence contains almost all primes. [_Charles R Greathouse IV_, Feb 26 2012] %o A122091 (PARI) p=2;forprime(q=3,1e5,if(q\10-p\10>1,print1(p", "));p=q) \\ _Charles R Greathouse IV_, Feb 26 2012 %Y A122091 Cf. A122072. %K A122091 nonn %O A122091 1,1 %A A122091 _Zak Seidov_, Oct 17 2006