BAEKJOON 1890

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {
	
	    public static void main(String[] args) throws Exception {
	 
	       BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	 
	        int n = Integer.parseInt(br.readLine());
	        int[][] arr = new int[n + 1][n + 1];
	        long[][] dp = new long[n + 1][n + 1];
	        for (int i = 0; i < n; i++) {
	            StringTokenizer st = new StringTokenizer(br.readLine());
	            for (int j = 0; j < n; j++) {
	                arr[i][j] = Integer.parseInt(st.nextToken());
	 
	            }
	        }
	        dp[0][0]=1;
	        for (int i = 0; i < n; i++) {
	            for (int j = 0; j < n; j++) {
	                if(i==n-1&&j==n-1) continue;
	                int next = arr[i][j];
	                if (i + next < n) {
	                    dp[i + next][j] += dp[i][j];
	                }
	                if (j + next < n) {
	                    dp[i][j + next] += dp[i][j];
	                }
	            }
	        }
	        System.out.println(dp[n-1][n-1]);
	    }
	}