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Problem 904


Problem 904


Pythagorean Angle

Given a right-angled triangle with integer sides, the smaller angle formed by the two medians drawn on the the two perpendicular sides is denoted by θ.

0904_Pythagorean_angle.jpg

Let f(α,L) denote the sum of the sides of the right-angled triangle minimizing the absolute difference between θ and α among all right-angled triangles with integer sides and hypotenuse not exceeding L.

If more than one triangle attains the minimum value, the triangle with the maximum area is chosen. All angles in this problem are measured in degrees.

For example, f(30,102)=198 and f(10,106)=1600158.

Define F(N,L)=n=1Nf(n3,L).

You are given F(10,106)=16684370.

Find F(45000,1010).


毕达哥拉斯角

给定一个各边长为整数的直角三角形,在其两条相互垂直的边上各画一条中线,这两条中线交叉所形成的较小角记为θ

0904_Pythagorean_angle.jpg

f(α,L)表示,在所有各边长为整数且斜边不超过L的直角三角形中,使θα的绝对差值最小的三角形的各边长之和。

如果最小绝对差值对应多个三角形,则选择其中面积最大的一个。本题中的所有角度均以度数表示。

例如,f(30,102)=198f(10,106)=1600158

定义F(N,L)=n=1Nf(n3,L)

已知F(10,106)=16684370

F(45000,1010)


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