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A175750
Numbers with 42 divisors.
4
2880, 4032, 4800, 6336, 7488, 9408, 9792, 10944, 11200, 13248, 14580, 15552, 15680, 16704, 17600, 17856, 20412, 20800, 21312, 23232, 23328, 23616, 24768, 27072, 27200, 30400, 30528, 32076, 32448, 33984, 34496, 35136, 36450, 36800, 37908, 38592, 38720, 40768
OFFSET
1,1
COMMENTS
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.
FORMULA
A000005(a(n))=42.
MATHEMATICA
Select[Range[50000], DivisorSigma[0, #]==42&] (* Vladimir Joseph Stephan Orlovsky, May 04 2011 *)
PROG
(PARI) is(n)=numdiv(n)==42 \\ Charles R Greathouse IV, Jun 19 2016
CROSSREFS
Sequence in context: A081427 A101999 A066174 * A179703 A260369 A134856
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Aug 27 2010
EXTENSIONS
Extended by T. D. Noe, May 08 2011
STATUS
approved