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Positive integers n for which the sum of the prime-factorization exponents of n (bigomega(n) = A001222(n)) divides n.
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%I #32 Jul 10 2020 03:49:56

%S 2,3,4,5,6,7,10,11,12,13,14,16,17,18,19,22,23,24,26,27,29,30,31,34,36,

%T 37,38,40,41,42,43,45,46,47,53,56,58,59,60,61,62,63,66,67,71,73,74,75,

%U 78,79,80,82,83,84,86,88,89,94,96,97,99,100,101,102,103,104,105,106

%N Positive integers n for which the sum of the prime-factorization exponents of n (bigomega(n) = A001222(n)) divides n.

%C If n is prime, trivially n is in the sequence.

%C The asymptotic density of this sequence is 0 (Erdős and Pomerance, 1990). - _Amiram Eldar_, Jul 10 2020

%H Keenan J. A. Down, <a href="/A074946/b074946.txt">Table of n, a(n) for n = 1..10000</a>

%H Paul Erdős and Carl Pomerance, <a href="https://math.dartmouth.edu/~carlp/PDF/paper79.pdf">On a theorem of Besicovitch: values of arithmetic functions that divide their arguments</a>, Indian J. Math., Vol. 32 (1990), pp. 279-287.

%F a(n) seems to be asymptotic to c*n*log(log(n)) with 1.128 < c < 1.13.

%t Select[Range[2, 120], Divisible[#, PrimeOmega[#]] &] (* _Jean-François Alcover_, Jun 08 2013 *)

%Y Cf. A001222, A134334 (complement).

%K easy,nonn

%O 1,1

%A _Benoit Cloitre_, Oct 05 2002

%E Revised definition from _Leroy Quet_, Sep 11 2008

%E More terms from _Keenan J. A. Down_, Dec 08 2016

%E Smaller boundary for 'c' from _Keenan J. A. Down_, Dec 08 2016