var fs = require('fs');
var length = fs.fstatSync(process.stdin.fd).size;
var buffer = Buffer.alloc(length);
var bytesRead = fs.readSync(process.stdin.fd, buffer, 0, length, 0);
var input = buffer.toString('utf8', 0, bytesRead);
var n=input-0;
//var n=(r[1].length);
var b=1;
var m=1000000007;
while(n--) {
    b=(b*10+3)%m;
}
console.log(b);