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A339812 Number of prime divisors of (A019565(n) - 1), counted with multiplicity.

%I A339812 #5 Dec 19 2020 07:59:32
%S A339812 0,1,1,2,2,2,1,2,1,3,1,2,2,4,2,2,2,5,2,4,1,3,2,3,3,3,1,8,1,2,1,3,2,2,
%T A339812 2,6,2,2,1,4,1,5,2,2,3,4,1,2,3,3,1,4,1,6,1,6,3,3,2,5,1,2,1,4,2,3,1,4,
%U A339812 2,2,1,2,2,3,2,5,2,4,2,3,1,6,2,2,3,3,2,4,1,3,1,5,2,2,2,4,4,2,3,6,2,2,2,2,2
%N A339812 Number of prime divisors of (A019565(n) - 1), counted with multiplicity.
%H A339812 Antti Karttunen, <a href="/A339812/b339812.txt">Table of n, a(n) for n = 1..65537</a>
%F A339812 a(n) = A001222(A339809(n)) = A001222(A019565(n)-1).
%F A339812 a(n) = A001222(A339810(n)).
%o A339812 (PARI)
%o A339812 A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };
%o A339812 A339812(n) = bigomega(A019565(n)-1);
%Y A339812 Cf. A001222, A019565, A339809, A339810.
%K A339812 nonn
%O A339812 1,4
%A A339812 _Antti Karttunen_, Dec 18 2020