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Number of prime divisors (with repetition) of the nonprimes (including 1).
7

%I #16 Mar 31 2023 21:40:36

%S 0,2,2,3,2,2,3,2,2,4,3,3,2,2,4,2,2,3,3,3,5,2,2,2,4,2,2,4,3,3,3,2,5,2,

%T 3,2,3,4,2,4,2,2,4,2,3,6,2,3,3,2,3,5,2,3,3,2,3,5,4,2,4,2,2,2,4,4,2,3,

%U 2,2,2,6,3,3,4,3,4,3,2,5,3,2,5,3,2,3,3,2,2,5,2,2,2,3,3,4,7,2,3,4,2,2,4,4,3

%N Number of prime divisors (with repetition) of the nonprimes (including 1).

%H Robert Israel, <a href="/A062502/b062502.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A001222(A018252(n)). - _Sean A. Irvine_, Mar 31 2023

%p f:= proc(n) if not isprime(n) then numtheory:-bigomega(n) fi end proc:

%p map(f, [$1..200]); # _Robert Israel_, Oct 01 2020

%t PrimeOmega/@Complement[Range[200],Prime[Range[PrimePi[200]]]] (* _Harvey P. Dale_, Apr 22 2011 *)

%o (PARI) je=[]; for(n=1,300, if(isprime(n), n+1,x=bigomega(n); je=concat(je,x))); je

%Y Cf. A001222, A018252.

%K nonn

%O 1,2

%A _Jason Earls_, Jul 09 2001