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Markov numbers that are semiprime.
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%I #7 May 16 2012 12:27:46

%S 34,169,194,985,4181,9077,14701,51641,135137,294685,499393,646018,

%T 925765,1136689,1346269,2012674,6625109,8399329,9647009,11485154,

%U 16964653,21531778,43484701,48928105,111242465,137295677,144059117,165580141,225058681,253191266

%N Markov numbers that are semiprime.

%C This is to A178444 as semiprimes A001358 are to primes A000040.

%F A001358 Intersection A002559. {x, y, or z satisfying x^2 + y^2 + z^2 = 3xyz, also such that A001222(of that number) = 2}.

%e 194 is in this sequence because it is a Markoff (or Markov) number, and 194 = 2 * 97.

%Y Cf. A001358, A002559, A178444.

%K nonn,easy

%O 1,1

%A _Jonathan Vos Post_, May 06 2012