Inscribed circles of triangles with one angle of 60 degrees
May 23, 2008
Let's call an integer sided triangle with exactly one angle of 60 degrees a 60-degree triangle. Let r be the radius of the inscribed circle of such a 60-degree triangle.
There are 1234 60-degree triangles for which r ≤ 100. Let T(n) be the number of 60-degree triangles for which r ≤ n, so T(100) = 1234, T(1000) = 22767, and T(10000) = 359912.
Find T(1053779).
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