package test;import java.io.*;import java.util.*;import java.math.*;public class Main{ public static void main(String Agrs[]) { BigInteger[] data = new BigInteger[300]; BigInteger two = new BigInteger("2"); Scanner cin = new Scanner(System.in); data[0] = new BigInteger("1"); data[1] = new BigInteger("1"); data[2] = new BigInteger("3"); for (int i = 3; i < 255; i++) { data[i] = (data[i-2].multiply(two).add(data[i-1])); } while (cin.hasNext()) { int n = cin.nextInt(); System.out.println(data[n]); } }}
