#include<iostream>
using namespace std;
int main(){
    int t;
    float k, b, m, d;
    cin>>t;
    cin>>k>>b;
    m=b-k;
    d=k-m;
    cout<<"an = "<<m<<"n + "<<"("<<d<<")"<<endl;
    cout<<"a"<<t<<" = "<<m*t+d;

}