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Highly composite numbers that are a product of two highly composite numbers greater than 1.
2

%I #12 Jul 08 2019 11:16:13

%S 4,12,24,36,48,120,240,360,720,1680,2520,5040,7560,10080,15120,20160,

%T 45360,50400,55440,110880,166320,221760,332640,498960,554400,665280,

%U 1441440,2162160,2882880,4324320,6486480,7207200,8648640,14414400,17297280,21621600,43243200,73513440

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

%H Amiram Eldar, <a href="/A307763/b307763.txt">Table of n, a(n) for n = 1..10000</a>

%e 7560 = 6 * 1260. 6 and 1260 are both highly composite numbers, so 7560 is in the sequence.

%t 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 Cf. A002182.

%K nonn

%O 1,1

%A _Dmitry Kamenetsky_, Apr 27 2019