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 A152588 #4 Sep 10 2016 14:14:28 %S A152588 17,227,50627,2562890627,6568408355712890627, %T A152588 43143988327398919500410556793212890627, %U A152588 1861403728794734215467410604755702820123364205073812627233564853668212890627 %N A152588 15^(2^n) + 2. %F A152588 a(n) = A175138(n+3)+2. - _R. J. Mathar_, Sep 10 2016 %o A152588 (PARI) g(a,n) = if(a%2,b=2,b=1);for(x=0,n,y=a^(2^x)+b;print1(y",")) %K A152588 nonn %O A152588 0,1 %A A152588 _Cino Hilliard_, Dec 08 2008