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A177871 Numbers n such that bigomega(n)^omega(n) > n. 1

%I

%S 60,120,210,420,840,1260,1680,2310,2730,3360,4620,5460,6930,7140,9240,

%T 10920,13860,14280,15960,16380,18480,21840,27720,28560,30030,31920,

%U 32760,36960,39270,43680,43890,46410,55440,57120,60060,73920,78540,87360,87780,90090,92820,103740,106260

%N Numbers n such that bigomega(n)^omega(n) > n.

%C bigomega(n) or Omega(n) is the number of prime divisors of n (counted with multiplicity): A001222, and omega(n) is the number of distinct primes dividing n: A001221.

%D J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 60, p. 22, Ellipses, Paris 2008.

%H Donovan Johnson, <a href="/A177871/b177871.txt">Table of n, a(n) for n = 1..500</a>

%e 120 is in the sequence because bigomega(120) = 5, omega(120) = 3, and 5^3 = 125 > 120.

%p with(numtheory): for n from 1 to 200000 do:if bigomega(n)^ nops(factorset(n))>

%p n then printf(`%d, `,n):else fi:od:

%t Select[Range[2, 10^5], PrimeOmega[#]^PrimeNu[#] > # &] (* From _Alonso del Arte_, Dec 13 2010 *)

%K nonn

%O 1,1

%A _Michel Lagneau_, Dec 13 2010

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Last modified November 14 04:56 EST 2019. Contains 329110 sequences. (Running on oeis4.)