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A048753 Composite numbers k whose product of aliquot divisors divided by number of aliquot divisors is an integer. 2

%I #18 Feb 14 2021 18:33:46

%S 4,6,15,16,20,21,27,33,36,39,42,45,48,50,51,56,57,69,70,75,87,93,100,

%T 105,111,120,123,129,132,141,154,159,162,175,177,182,183,189,196,198,

%U 201,210,213,219,220,231,237,238,245,249,256,266,267,270,273,275,291

%N Composite numbers k whose product of aliquot divisors divided by number of aliquot divisors is an integer.

%H Amiram Eldar, <a href="/A048753/b048753.txt">Table of n, a(n) for n = 1..10000</a>

%e For k=6, the product of aliquot divisors is 3*2*1=6; the number of aliquot divisors is 3; 6/3 = 2 (an integer), so 6 is a term.

%t padQ[n_]:=Module[{ad=Most[Divisors[n]]},!PrimeQ[n]&&Divisible[Times@@ad, Length[ad]]]; Select[Range[2,300],padQ] (* _Harvey P. Dale_, May 07 2012 *)

%Y Cf. A007956, A032741, A048752, A048754.

%K easy,nonn

%O 1,1

%A _Enoch Haga_

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Last modified April 19 12:14 EDT 2024. Contains 371792 sequences. (Running on oeis4.)