Factorial.java Computes an exact factorial, n!, using a BigInteger

import java.math.BigInteger;

/** Computes an exact factorial, using a BigInteger.
 *
 *  Taken from Core Web Programming from
 *  Prentice Hall and Sun Microsystems Press,
 *  .
 *  © 2001 Marty Hall and Larry Brown;
 *  may be freely used or adapted.
 */

public class Factorial {
  public static void main(String[] args) {
    for(int i=1; i<=256; i*=2) {
      System.out.println(i + "!=" + factorial(i));
    }
  }

  public static BigInteger factorial(int n) {
    if (n <= 1) {
      return(new BigInteger("1"));
    } else {
      BigInteger bigN = new BigInteger(String.valueOf(n));
      return(bigN.multiply(factorial(n - 1)));
    }
  }
}