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diff --git a/challenge-169/roger-bell-west/python/ch-2.py b/challenge-169/roger-bell-west/python/ch-2.py
new file mode 100755
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+++ b/challenge-169/roger-bell-west/python/ch-2.py
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+#! /usr/bin/python3
+
+import unittest
+
+from math import sqrt,floor,gcd
+from collections import deque
+from functools import reduce
+
+def genprimes(mx):
+  primesh=set(range(2,4))
+  for i in range(6,mx+2,6):
+    for j in range(i-1,i+2,2):
+      if j <= mx:
+        primesh.add(j)
+  q=deque([2,3,5,7])
+  p=q.popleft()
+  mr=floor(sqrt(mx))
+  while p <= mr:
+    if p in primesh:
+      for i in range(p*p,mx+1,p):
+        primesh.discard(i)
+    if len(q) < 2:
+      q.append(q[-1]+4)
+      q.append(q[-1]+2)
+    p=q.popleft()
+  primes=list(primesh)
+  primes.sort()
+  return primes
+
+def primefactor(n):
+  f=dict()
+  m=n
+  for p in genprimes(floor(sqrt(n))):
+    while (m % p == 0):
+      m //= p
+      if p in f:
+        f[p] += 1
+      else:
+        f[p] = 1
+    if m==1:
+      break
+  if m > 1:
+    if m in f:
+      f[m] += 1
+    else:
+      f[m] = 1
+  return f
+
+def achilles(ct):
+  o = []
+  n = 1
+  while True:
+    n += 1
+    pv = [i for i in primefactor(n).values()]
+    if len(pv) > 1 and min(pv) >= 2 and reduce(gcd,pv,pv[0]) == 1:
+       o.append(n)
+       if len(o) >= ct:
+         break
+  return o
+
+class TestAchilles(unittest.TestCase):
+
+        def test_ex1(self):
+          self.assertEqual(achilles(20),
+                           [72, 108, 200, 288, 392, 432, 500, 648,
+                            675, 800, 864, 968, 972, 1125, 1152, 1323,
+                            1352, 1372, 1568, 1800],
+                           'example 1')
+
+unittest.main()