cp's OEIS Frontend

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.

A307763 Highly composite numbers that are a product of two highly composite numbers greater than 1.

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%I A307763 #12 Jul 08 2019 11:16:13
%S A307763 4,12,24,36,48,120,240,360,720,1680,2520,5040,7560,10080,15120,20160,
%T A307763 45360,50400,55440,110880,166320,221760,332640,498960,554400,665280,
%U A307763 1441440,2162160,2882880,4324320,6486480,7207200,8648640,14414400,17297280,21621600,43243200,73513440
%N A307763 Highly composite numbers that are a product of two highly composite numbers greater than 1.
%H A307763 Amiram Eldar, <a href="/A307763/b307763.txt">Table of n, a(n) for n = 1..10000</a>
%e A307763 7560 = 6 * 1260. 6 and 1260 are both highly composite numbers, so 7560 is in the sequence.
%t A307763 hcQ[n_, v_] := AnyTrue[v, MemberQ[v, n/#] &]; hc = {}; s = {}; dm = 0; Do[d = DivisorSigma[0, n]; If[d > dm, dm = d; If[hcQ[n, hc], AppendTo[s, n]]; AppendTo[hc, n]], {n, 10^7}]; s (* _Amiram Eldar_, Jul 05 2019 *)
%Y A307763 Cf. A002182.
%K A307763 nonn
%O A307763 1,1
%A A307763 _Dmitry Kamenetsky_, Apr 27 2019