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Numbers of the form of 4x^2 - 4xy + 7y^2 (=24k+7) but not of the form 4x^2 + 4xy + 7y^2.
2

%I #3 Mar 31 2012 10:22:09

%S 151,487,727,751,1039,1063,1399,1471,1759,1783,2287,2647,2671,2767,

%T 3343,3463,3919,4111,4423,4663,4903,4999,5167,5407,5791,6607,6703,

%U 6823,7159,7351,7639,7879,8191,8263,8311,8839,9127,9151,9439,9967,10111,10711

%N Numbers of the form of 4x^2 - 4xy + 7y^2 (=24k+7) but not of the form 4x^2 + 4xy + 7y^2.

%C Numbers which occur in A107006 but not in A107005.

%Y Cf. A107005, A107006.

%K nonn

%O 1,1

%A _Artur Jasinski_, Apr 28 2008

%E More terms from _T. D. Noe_, May 01 2008