updating DIRECTORY.md

Author: github-actions

DIRECTORY.md

@@ -109,6 +109,7 @@
   * [AbsoluteMax](https://github.com/TheAlgorithms/Java/blob/master/Maths/AbsoluteMax.java)
   * [AbsoluteMin](https://github.com/TheAlgorithms/Java/blob/master/Maths/AbsoluteMin.java)
   * [AbsoluteValue](https://github.com/TheAlgorithms/Java/blob/master/Maths/AbsoluteValue.java)
+  * [AmicableNumber](https://github.com/TheAlgorithms/Java/blob/master/Maths/AmicableNumber.java)
   * [Factorial](https://github.com/TheAlgorithms/Java/blob/master/Maths/Factorial.java)
   * [FactorialRecursion](https://github.com/TheAlgorithms/Java/blob/master/Maths/FactorialRecursion.java)
   * [FibonacciNumber](https://github.com/TheAlgorithms/Java/blob/master/Maths/FibonacciNumber.java)
@@ -127,6 +128,7 @@
   * [PowRecursion](https://github.com/TheAlgorithms/Java/blob/master/Maths/PowRecursion.java)
   * [PrimeCheck](https://github.com/TheAlgorithms/Java/blob/master/Maths/PrimeCheck.java)
   * [PrimeFactorization](https://github.com/TheAlgorithms/Java/blob/master/Maths/PrimeFactorization.java)
+  * [VampireNumber](https://github.com/TheAlgorithms/Java/blob/master/Maths/VampireNumber.java)
 
 ## MinimizingLateness
   * [MinimizingLateness](https://github.com/TheAlgorithms/Java/blob/master/MinimizingLateness/MinimizingLateness.java)