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 A247870 #17 Oct 15 2014 15:55:27 %S A247870 7,5,11,5,13,5,7,11,5,17,7,5,13,11,5,7,19,5,7,17,5,5,29,5,11,7,13,5, %T A247870 17,7,5,11,31,5,7,23,5,19,7,5,29,13,5,11,5,7,5,23,13,7,5,5,7,43,5,11, %U A247870 17,7,19,5,23,5,11,13,5,41,7,47,17,5,31,11,7,5,13,29,5,7,23,37,11,5,17,7,13,5,43,19,5,5,7,17,5,11 %N A247870 Least prime factor of odd numbers congruent to 4 modulo 9. %H A247870 Odimar Fabeny, <a href="/A247870/b247870.txt">Table of n, a(n) for n = 1..10000</a> %Y A247870 Cf. A056608, A247678. %K A247870 nonn,easy %O A247870 1,1 %A A247870 _Odimar Fabeny_, Sep 25 2014