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Recursive highly composite numbers: numbers with a record number of recursive divisors (A282446).
4

%I #7 Apr 11 2020 05:36:35

%S 1,2,4,6,12,30,36,60,180,420,900,1260,4620,6300,13860,44100,55440,

%T 69300,180180,485100,720720,900900,2882880,3063060,6306300,12252240,

%U 15315300,49008960,58198140,107207100,232792560,290990700,931170240,1163962800,2036934900,4655851200

%N Recursive highly composite numbers: numbers with a record number of recursive divisors (A282446).

%C The corresponding record values are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 27, 36, 48, 54, ...

%H Amiram Eldar, <a href="/A333931/b333931.txt">Table of n, a(n) for n = 1..200</a>

%t recDivNum[1] = 1; recDivNum[n_] := recDivNum[n] = Times @@ (1 + recDivNum/@ (Last /@ FactorInteger[n])); rm = 0; s = {}; Do[r = recDivNum[n]; If[r > rm, rm = r; AppendTo[s, n]], {n, 1, 10^4}]; s

%Y Subsequence of A025487.

%Y Cf. A282446.

%Y Analogous sequences: A002182 (highly composite), A002110 (unitary), A037992 (infinitary), A293185 (bi-unitary), A309141 (nonunitary), A318278 (exponential).

%K nonn

%O 1,2

%A _Amiram Eldar_, Apr 10 2020