Answer:
{ x : x = 2^n -1 , n ∈ N}
Where N is the set of natural numbers
Step-by-step explanation:
Mathematically, we can rewrite each term in the set as follows;
1 = 2^1 - 1
3 = 2^2 -1
7 = 2^3 -1
15 = 2^4-1
31 = 2^5-1
63 = 2^6 -1
so we can conclude that the nth term is 2^n -1
So writing this in set builder notation, we have;
{ x : x = 2^n -1 , n ∈ N}
Where N is the set of natural numbers