1,3,7,15,31,63,127…… What is n

1,3,7,15,31,63,127…… What is n

Hello!
01-1 of 1 = 2
3=2²-1
7=2³-1
The fourth power of 15 = 2-1
The fifth power of 31 = 2-1
The sixth power of 63 = 2-1
127 = 2 to the 7th power - 1
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The nth power of n = 2-1
I hope my answer will help you