Problem 195

Inscribed circles of triangles with one angle of 60 degrees

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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These problems are part of
Project Euler
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