{"app":{"locale":"en-GB"},"problem":{"content":"

In the following equation x, y, and n are positive integers.

$$\\dfrac{1}{x} + \\dfrac{1}{y} = \\dfrac{1}{n}$$

For a limit L we define F(L) as the number of solutions which satisfy x < y ≤ L.

We can verify that F(15) = 4 and F(1000) = 1069.
Find F(10¹²).

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