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 A129615 #2 Mar 30 2012 17:37:44 %S A129615 1,1,15,385,137593,106908087 %N A129615 a(n) is the smallest natural number m such that 4^4^k + m is prime for k=0,1,...,n. %C A129615 Next term is greater than 3*10^8. %e A129615 For k=0,1,...,5 4^4^k + 106908087 are prime and 106908087 is the smallest number with this property so a(5)=106908087. %Y A129615 Cf. A129613, A129614. %K A129615 hard,more,nonn %O A129615 0,3 %A A129615 _Farideh Firoozbakht_, May 13 2007