First commit

Cryptotools/Numbers/coprime.py

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+#!/usr/bin/env python3
+
+from Cryptotools.Utils.utils import gcd
+
+
+# https://oeis.org/A000010
+def phi(n):
+    """
+        This function count all phi(n)
+
+        Args:
+            n (integer): it's the phi(n) value
+
+        Returns:
+            Return the phi(n)
+    """
+    y = 1
+    for i in range(2, n):
+        if gcd(n, i) == 1:
+            y += 1
+    return y
+