Added pascal_triangle.py

Author: VarunS2002

pascal_triangle.py

@@ -0,0 +1,20 @@
+from permutations_combinations import PermutationsCombinations
+
+
+class PascalTriangle:
+    @staticmethod
+    def pascal_triangle(rows: int) -> None:
+        if not isinstance(rows, int):
+            raise ArithmeticError("Number of rows in a Pascal's triangle cannot be non-integers.")
+        elif rows < 0:
+            raise ArithmeticError("Number of rows in a Pascal's triangle cannot be negative.")
+        for n in range(rows):
+            for r in range(rows - n + 1):
+                print(end="  ")
+            for r in range(n + 1):
+                print(PermutationsCombinations.ncr(n, r), end='   ' if r != n else '')
+            print()
+
+
+if __name__ == '__main__':
+    PascalTriangle.pascal_triangle(int(input("Enter the number of rows: ")))