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%I #19 Sep 08 2022 08:45:05
%S 1,1,2,2,4,4,6,5,7,8,10,9,12,12,13,12,16,15,18,17,19,20,22,20,23,24,
%T 24,25,28,27,30,27,31,32,33,32,36,36,37,36,40,39,42,41,42,44,46,43,47,
%U 47,49,49,52,50,53,52,55,56,58,56,60,60,60,58
%N n minus the number of its prime-factors: a(n) = n - A001222(n).
%C Prime factors are counted with multiplicity. [_Harvey P. Dale_, Sep 20 2011]
%H Vincenzo Librandi, <a href="/A069345/b069345.txt">Table of n, a(n) for n = 1..5000</a>
%t Table[n-PrimeOmega[n],{n,70}] (* _Harvey P. Dale_, Sep 20 2011 *)
%o (PARI) a(n) = n - bigomega(n); \\ _Michel Marcus_, Apr 08 2018
%o (Magma) [n eq 1 select 1 else n-(&+[p[2]: p in Factorization(n)]): n in [1..100]]; // _Vincenzo Librandi_, Apr 09 2018
%Y Cf. A001222, A064800, A069355.
%K nonn
%O 1,3
%A _Reinhard Zumkeller_, Mar 18 2002