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Problem 223

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Almost right-angled triangles I

Let us call an integer sided triangle with sides a ≤ b ≤ c barely acute if the sides satisfy a² + b² = c² + 1.

How many barely acute triangles are there with perimeter ≤ 25,000,000?

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几乎直角的三角形I

如果一个边长为整数a ≤ b ≤ c的三角形满足a² + b² = c² + 1，我们称其为略微锐角的三角形。

有多少个周长≤ 25,000,000的略微锐角三角形？

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