uva673 Parentheses Balance

import java.util.*;
import java.io.*;
import java.math.*;

public class poj_1205 {
public static void main(String[] args){
BigInteger f[]=new BigInteger[110];
f[1]=BigInteger.valueOf(1);
f[2]=BigInteger.valueOf(3);
for(int i=3;i<=100;i++){
f[i]=(f[i-1].multiply(BigInteger.valueOf(3))).subtract(f[i-2]);
}
Scanner cin=new Scanner(System.in);
while(cin.hasNext()){
int n=cin.nextInt();
System.out.println(f
);
}
}
}