Question

write a program in C++ for the function a(n)=((2n+1)/(2n!)^2)

Answer 1

#include <iostream>
using namespace std;

long double calc(int n) {
long double res = (2*n + 1) / 4.0;
for (int i = 2; i <= n; i++)
& res /= i*i;
return res;
}

int main() {
cout << "Input n: ";
int n;
cin >> n;
cout << "(2n+1)/(2n!)^2 = " << calc(n) << endl;
}