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 A275239 #27 Apr 06 2020 03:15:06 %S A275239 3,8,16,18,30,72,144,168,252,336,420,900,960,1008,1080,1440,2160,2880, %T A275239 3360,6300,6720,7920,9240,12600,18480,30240,60480,65520,98280,131040, %U A275239 196560,262080,327600,360360,589680,655200,786240,831600,1108800,1330560,1663200 %N A275239 Highly composite numbers of class 1 (see comment). %C A275239 Consider the sequence of highly composite numbers (HCN) (A002182). Let us say that its terms are HCN of class 0. Removing A002182 from the positive integers we obtain the sequence 3,5,7,8,9,10,11,13,14,15,16,17,18,...(1) %C A275239 Consider the subsequence whose number of divisors set a record. We obtain 3,8,16,18,... We call this sequence HCN of class 1. It is A275239. %C A275239 Furthermore, removing from sequence (1) the HCN of class 1 we obtain the sequence 5,7,9,10,11,13,14,15,17,19,20,21,... (2) %C A275239 Again consider the subsequence whose number of divisors are records. We obtain 5,9,10,20,... We call this sequence HCN of class 2. It is A275240, etc. %C A275239 Note that the sequence of HCN of class h>=1 numbers begins from Prime(h+1)(which is the unique prime in the sequence). %H A275239 Amiram Eldar, <a href="/A275239/b275239.txt">Table of n, a(n) for n = 1..78</a> (terms below 10^10) %Y A275239 Cf. A002182, A275240, A275241, A275242, A275243, A275244. %K A275239 nonn %O A275239 1,1 %A A275239 _Vladimir Shevelev_ and _Peter J. C. Moses_, Jul 21 2016