Given n ϵ N and n<4
So, n = 1, 2, 3.
Also, x=n2n+1
Substituting n = 1, 2, 3 we get,
x=12(1)+1=13
x=22(2)+1=25
x=32(3)+1=37
∴ The required set is A = {13,25,37}
The roster form of the set A={x:x=n2n+1, n∈N and n<4} is ___. (Here, N stands for the set of natural numbers)