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%I #27 Dec 11 2021 04:57:18
%S 0,1,2,2,4,3,6,4,4,5,10,4,12,7,6,5,16,5,18,6,8,11,22,6,8,13,6,8,28,7,
%T 30,6,12,17,10,6,36,19,14,7,40,9,42,12,8,23,46,7,12,9,18,14,52,7,14,9,
%U 20,29,58,8,60,31,10,8,16,13,66,18,24,11,70,9,72,37,10,20,16,15,78,9,8,41
%N Number of prime factors (counted with multiplicity) of the smallest number with exactly n divisors.
%C This function is not additive; the smallest counterexample is a(40) = 7 != 4 + 4 = a(5) + a(8). - _Franklin T. Adams-Watters_ Jul 10 2009
%H David A. Corneth, <a href="/A122376/b122376.txt">Table of n, a(n) for n = 1..10000</a> (first 2000 terms from Amiram Eldar)
%F a(n) = Omega(A005179(n)), where Omega(n) = A001222(n).
%F a(p) = p-1 for prime p.
%F a(n) = A001222(A130279(n))/2. - _Reinhard Zumkeller_, May 21 2007
%t s = { (* terms in A005179 *) }; f[n_] := Plus @@ Last /@ FactorInteger@n; f /@ s (* _Robert G. Wilson v_, Aug 31 2006 *)
%Y Cf. A001222, A005179, A130279.
%K nonn
%O 1,3
%A _Lekraj Beedassy_, Aug 30 2006
%E More terms from _Robert G. Wilson v_, Aug 31 2006
%E Edited and extended by _Ray Chandler_, Sep 11 2006
%E Incorrect comment removed by _Franklin T. Adams-Watters_, Jul 11 2009
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