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 A173417 #2 Mar 30 2012 18:52:39 %S A173417 1,7,12,14,16,20,21,22,24,25,27,28,29,33,35,39,40,41,44,45,47,49,52, %T A173417 53,54,55 %N A173417 Either A162488(n)-+A162489(n) is prime. %C A173417 Where A162488 are numbers x such that x^y+y^x is prime (for some y>1, y<x) and A162489 is least y such that x^y+y^x is prime (for x=A162488(n)). %e A173417 a(1)=1 because A162488(1)-A162489(1)=1=nonprime and A162488(1)+A162489(1)=5=prime; a(2)=7 because A162488(7)-A162489(7)=31=prime and A162488(7)+A162489(7)=35=nonprime. %Y A173417 Cf. A094133, A162488, A162489. %K A173417 nonn %O A173417 1,2 %A A173417 _Juri-Stepan Gerasimov_, Mar 02 2010