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Omega(n+1) = 2*Omega(n), where Omega(n) is the number of prime divisors of n (with repetition).
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%I #10 Dec 15 2017 17:35:22

%S 3,5,13,15,35,37,39,55,61,63,73,87,134,155,157,183,193,203,209,219,

%T 247,249,259,277,295,305,313,314,327,329,339,341,371,397,399,413,421,

%U 457,458,471,489,515,535,539,541,545,579,583,613,635,649,661,673,685,689

%N Omega(n+1) = 2*Omega(n), where Omega(n) is the number of prime divisors of n (with repetition).

%H Harry J. Smith, <a href="/A063484/b063484.txt">Table of n, a(n) for n=1,...,1000</a>

%e Omega(949)=2, Omega(949+1)=2*2, so 949 is a member of the sequence.

%o (PARI) j=[]; for(n=1,1000, if(bigomega(n+1)==2*bigomega(n),j=concat(j,n))); j

%o (PARI) { n=0; for (m=1, 10^9, if (bigomega(m + 1) == 2*bigomega(m), write("b063484.txt", n++, " ", m); if (n==1000, break)) ) } \\ _Harry J. Smith_, Aug 23 2009

%K nonn

%O 1,1

%A _Jason Earls_, Jul 28 2001