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How to make four 7 s equal to 4 and to 10?

f(7, 7, 7, 7) = 1: 7/7 * 7/7 = 1

f(7, 7, 7, 7) = 2: 7/7 + 7/7 = 2

f(7, 7, 7, 7) = 3: (7+7+7)/7 = 3

f(7, 7, 7, 7) = 4: ?

.

.

f(7, 7, 7, 7) = 10: ?

I can also make four 7s equal to 5, 6 , 7 , 8 and 9 by using square root and lg plus +, – * and / but not 4 and 10.

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$$\frac{77}{7}- 7=4$$

$$\frac{77-7}{7}=10$$

How about this: $|\{7,7,7,7\}|=4$. Seems obvious but don’t know if it falls in line with acceptable mathematical operations!

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