Competitions
Биномиальный коэффициент
Sum of squares Cnk
Given a non-negative integer n, find the sum of binomial coefficients
Input
One non-negative integer n (n ≤ 30).
Output
Print the sum value.
Input example #1
3
Output example #1
20
Given a non-negative integer n, find the sum of binomial coefficients
One non-negative integer n (n ≤ 30).
Print the sum value.
3
20