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A063464 omega(n) = omega(n+2), where omega(n) is the number of distinct prime divisors of n. 2

%I

%S 2,3,5,7,9,10,11,12,17,18,20,22,23,24,25,26,27,29,33,34,36,38,41,44,

%T 46,47,48,50,52,54,55,56,59,63,71,72,74,75,79,80,81,85,86,91,92,93,94,

%U 96,98,101,104,106,107,115,116,117,122,125,130,133,134,137,138,141,142

%N omega(n) = omega(n+2), where omega(n) is the number of distinct prime divisors of n.

%H Harry J. Smith, <a href="/A063464/b063464.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[200],PrimeNu[#]==PrimeNu[#+2]&] (* _Harvey P. Dale_, Jun 20 2011 *)

%o (PARI) j=[]; for(n=1,350, if(omega(n)==omega(n+2),j=concat(j,n))); j

%o (PARI) { n=0; for (m=1, 10^9, if (omega(m) == omega(m + 2), write("b063464.txt", n++, " ", m); if (n==1000, break)) ) } [_Harry J. Smith_, Aug 22 2009]

%K nonn

%O 1,1

%A _Jason Earls_, Jul 26 2001

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Last modified January 23 22:46 EST 2022. Contains 350515 sequences. (Running on oeis4.)