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 A201460 #5 Mar 30 2012 18:36:00
%S A201460 1,15,1,19,51,1,49,1,1,15,51,9,21,211,79,21,7,31,129,105,87,21,21,13,
%T A201460 7,109,57,55,159,75,231,73,33,19,57,75,3,49,207,93,463,15,141,421,151,
%U A201460 177,237,1,99,49,129,211,79,697,49,13,237,169,439,181,201,109,159,229,271,15,31,559,57,127,183,595,43,237,3,69,463,387,141
%N A201460 Least k such that (7^n - k)*7^n + 1 is a prime number.
%t A201460 Table[k = 0; While[!PrimeQ[(7^n - k)*7^n + 1], k++]; k, {n, 85}]
%Y A201460 Cf. A191619, A200923, A201131.
%K A201460 nonn
%O A201460 1,2
%A A201460 _Michel Lagneau_, Dec 01 2011