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 A036320 #22 May 22 2022 05:50:56
%S A036320 25,35,49,125,175,245,343,625,875,1225,1715,2401,2785,2885,3125,3785,
%T A036320 3899,4039,4375,5299,6125,8575,12005,13925,14425,15625,16807,18925,
%U A036320 19495,20195,21875,26495,27293,27785,28273,30625,37093,37885,38785
%N A036320 Composite numbers whose prime factors contain no digits other than 5 and 7.
%C A036320 All terms are a product of at least two terms of A020467. - _David A. Corneth_, Oct 09 2020
%H A036320 David A. Corneth, <a href="/A036320/b036320.txt">Table of n, a(n) for n = 1..10000</a>
%H A036320 <a href="/index/Pri#prime_factors">Index entries for sequences related to prime factors</a>.
%F A036320 Sum_{n>=1} 1/a(n) = Product_{p in A020467} (p/(p - 1)) - Sum_{p in A020467} 1/p - 1 = 0.1179595738... . - _Amiram Eldar_, May 22 2022
%Y A036320 Cf. A003595, A020467, A036302-A036325.
%K A036320 nonn,easy,base
%O A036320 1,1
%A A036320 _Patrick De Geest_, Dec 15 1998