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%I #16 Aug 14 2015 01:18:39
%S 2,5,6,7,8,10,11,13,14,15,17,18,19,20,21,22,23,24,26,28,29,30,31,32,
%T 33,34,35,37,38,39,40,41,42,43,44,45,46,47,50,51,52,53,54,55,56,57,58,
%U 59,60,61,62,63,65,66,67,68,69,70,71,72,73,74,76,77,78,79,80,82,83,84
%N Positive integers that are not of the form n^2 or 3n^2.
%C Values of n such that Q(sqrt(-n)) has 2 units.
%C A214295(a(n)) = 0. - _Reinhard Zumkeller_, Jul 12 2012
%H Reinhard Zumkeller, <a href="/A092206/b092206.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Unit.html">Unit</a>
%t Select[ Range[100], Not[ IntegerQ[ Sqrt[#] ] || IntegerQ[ Sqrt[#/3] ] ]&] (* _Jean-François Alcover_, Oct 30 2012 *)
%o (Haskell)
%o a092206 n = a092206_list !! (n-1)
%o a092206_list = filter ((== 0) . a214295) [1..]
%o -- _Reinhard Zumkeller_, Jul 12 2012
%o (PARI) is(n)=!issquare(n/3^valuation(n,3)) \\ _Charles R Greathouse IV_, Oct 30 2012
%Y Cf. A000290, A033428, A092205.
%K nonn
%O 1,1
%A _Eric W. Weisstein_, Feb 24 2004
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