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 A209839 #7 Mar 31 2012 10:30:50
%S A209839 1,3,7,13,15,21,25,27,31,37,43,45,51,55,57,63,67,73,81,85,87,91,93,97,
%T A209839 111,115,121,123,133,135,141,147,151,157,163,165,175,177,181,183,195,
%U A209839 207,211,213,217,223,225,235,241,247,253,1330,1383,4179,4180,4181,5243,12985,48506,87161,211750
%N A209839 Integers n such that for all i > n the largest prime factor of product(i+k, {k,0,15}) exceeds the largest prime factor of product(n+k, {k,0,15}).
%C A209839 Heuristics show that these terms are valid, but a strict proof is yet to be done.
%H A209839 Andrey V. Kulsha, <a href="/A209839/b209839.txt">Table of n, a(n) for n = 1..80</a>
%Y A209839 Cf. A209838.
%K A209839 nonn
%O A209839 1,2
%A A209839 _Andrey V. Kulsha_, Mar 14 2012