Harmonic Geometric and P-Series Added (#1633)

* Harmonic Geometric and P-Series Added

* Editing comments

* Update and rename series/Geometric_Series.py to maths/series/geometric_series.py

* Update and rename series/Harmonic_Series.py to maths/series/harmonic_series.py

* Update and rename series/P_Series.py to maths/series/p_series.py

maths/series/harmonic_series.py

@@ -0,0 +1,46 @@
+"""
+This is a pure Python implementation of the Harmonic Series algorithm
+https://en.wikipedia.org/wiki/Harmonic_series_(mathematics)
+
+For doctests run following command:
+python -m doctest -v harmonic_series.py
+or
+python3 -m doctest -v harmonic_series.py
+
+For manual testing run:
+python3 harmonic_series.py
+"""
+
+
+def harmonic_series(n_term: str) -> list:
+    """Pure Python implementation of Harmonic Series algorithm
+
+    :param n_term: The last (nth) term of Harmonic Series
+    :return: The Harmonic Series starting from 1 to last (nth) term
+
+    Examples:
+    >>> harmonic_series(5)
+    ['1', '1/2', '1/3', '1/4', '1/5']
+    >>> harmonic_series(5.0)
+    ['1', '1/2', '1/3', '1/4', '1/5']
+    >>> harmonic_series(5.1)
+    ['1', '1/2', '1/3', '1/4', '1/5']
+    >>> harmonic_series(-5)
+    []
+    >>> harmonic_series(0)
+    []
+    >>> harmonic_series(1)
+    ['1']
+    """
+    if n_term == "":
+        return n_term
+    series = []
+    for temp in range(int(n_term)):
+        series.append(f"1/{temp + 1}" if series else "1")
+    return series
+
+
+if __name__ == "__main__":
+    nth_term = input("Enter the last number (nth term) of the Harmonic Series")
+    print("Formula of Harmonic Series => 1+1/2+1/3 ..... 1/n")
+    print(harmonic_series(nth_term))