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 A069179 #5 Oct 19 2017 03:14:00 %S A069179 4,6,211050,253680,41887255410,73768891456260 %N A069179 Least number X such that for each k in (0 to n-1), 2^k*X-1 and 2^k*X+1 are primes. That is, there are N twin primes, each the "double" of the previous. %C A069179 a(6)=73768891456260 might be called a(6.5), since 64*a(6)+1 is prime. But 64*a(6)-1 is 167*1021*44533*621769, alas. %e A069179 a(3) = 211050 because 1*a(3)-1, 1*a(3)+1, 2*a(3)-1, 2*a(3)+1, 4*a(3)-1 and 4*a(3)+1 are all prime. %Y A069179 Equals A068635 + 1. %K A069179 nonn %O A069179 1,1 %A A069179 _Don Reble_, Apr 09 2002