Best Irrational Numbers

These are the greatest irrational numbers ever. They are helpful or just long and tedious. Let's vote and see.
The Top Ten
1 The Golden Ratio
2 Pi
3 e
4 square root of 3
5 square root of 2
6 square root of 5
7 Pi square
8 square root of 7
9 Pi/2
10 The golden ratio* root 2
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