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 A133449 #6 Mar 31 2012 13:22:05 %S A133449 9561,924591,10306101,40379541,45964621,13860931,97601931,206197461, %T A133449 39350401,70495851,736139881,120414601,614399751,422650131,862677661, %U A133449 5344474491,1622536021,502698841,3425985241,806838691,4484608141 %N A133449 Least K such that 10^(10*n-1) + K + 6*s are consecutive primes for s=0, s=1, s=2, s=3. %e A133449 10^9+9561, 10^9+9561+6, 10^9+9561+12, 10^9+9561+18 are consecutive primes so K(1)=9561 (no number < 9561 give 4 consecutive primes). %K A133449 hard,nonn %O A133449 1,1 %A A133449 _Pierre CAMI_, Nov 27 2007 %E A133449 a(6)-a(10) corrected and a(11)-a(21) added by _Donovan Johnson_, Nov 11 2008