Merge remote-tracking branch 'upstream/master'

# Conflicts:
#	challenge-160/paulo-custodio/Makefile

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diff --git a/challenge-159/lubos-kolouch/python/ch-1.py b/challenge-159/lubos-kolouch/python/ch-1.py
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+++ b/challenge-159/lubos-kolouch/python/ch-1.py
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+""" Challenge 159 Task 1"""
+
+
+def farey_sequence(n: int, descending: bool = False) -> str:
+    """Print the n'th Farey sequence. Allow for either ascending or descending."""
+    (a, b, c, d) = (0, 1, 1, n)
+
+    solution = []
+    if descending:
+        (a, c) = (1, n - 1)
+    solution.append(f"{a}/{b}")
+    while (c <= n and not descending) or (a > 0 and descending):
+        k = (n + b) // d
+        (a, b, c, d) = (c, d, k * c - a, k * d - b)
+        solution.append(f"{a}/{b}")
+
+    return ", ".join(solution)
+
+
+assert farey_sequence(5) == "0/1, 1/5, 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5, 1/1"