New answers tagged quadratic-forms
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Integers $8k+3>0$ not represented by $2x^2+4y^2+4yz+9z^2$ over the integers
First things first, all the relevant numbers really are represented by $x^2 + 2 y^2 + 32 z^2.$ See http://zakuski.math.utsa.edu/~kap/Kap_Jagy_Schiemann_1997.pdf
for regular ternaries.
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