A175750 - OEIS

%I #21 May 05 2023 10:04:11

%S 2880,4032,4800,6336,7488,9408,9792,10944,11200,13248,14580,15552,

%T 15680,16704,17600,17856,20412,20800,21312,23232,23328,23616,24768,

%U 27072,27200,30400,30528,32076,32448,33984,34496,35136,36450,36800,37908,38592,38720,40768

%N Numbers with 42 divisors.

%C Numbers of the forms p^41, p^20*q^1, p^13*q^2, p^6*q^5 and p^6*q^2*r^1 (A179703), where p, q, and r are distinct primes.

%H T. D. Noe, <a href="/A175750/b175750.txt">Table of n, a(n) for n = 1..1000</a>

%H OEIS Wiki, <a href="https://oeis.org/wiki/Index_entries_for_number_of_divisors">Index entries for number of divisors</a>

%F A000005(a(n))=42.

%t Select[Range[50000],DivisorSigma[0,#]==42&] (* _Vladimir Joseph Stephan Orlovsky_, May 04 2011 *)

%o (PARI) is(n)=numdiv(n)==42 \\ _Charles R Greathouse IV_, Jun 19 2016

%Y Cf. A137484, A137488.

%K nonn

%O 1,1

%A _Jaroslav Krizek_, Aug 27 2010

%E Extended by _T. D. Noe_, May 08 2011