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Martin Sleziak
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The outer Nagel points and unknown central circle

Na, Nb, Nc are the outer Nagel points. A'B'C' is the contact triangle. I claim that lines A'B', A'C', B'C' always cut the sides of the triangle NaNbNc at six points corresponding to an unknown circle. Surprisingly its center is not defined in the ETC:

unknown central circle

Is it safe to say that this is actually the new central circle associated with the triangle ABC?

A.Zakharov
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