Data commit

Task/Fractran/Python/fractran-1.py

@@ -0,0 +1,21 @@
+from fractions import Fraction
+
+def fractran(n, fstring='17 / 91, 78 / 85, 19 / 51, 23 / 38, 29 / 33,'
+                        '77 / 29, 95 / 23, 77 / 19, 1 / 17, 11 / 13,'
+                        '13 / 11, 15 / 14, 15 / 2, 55 / 1'):
+    flist = [Fraction(f) for f in fstring.replace(' ', '').split(',')]
+
+    n = Fraction(n)
+    while True:
+        yield n.numerator
+        for f in flist:
+            if (n * f).denominator == 1:
+                break
+        else:
+            break
+        n *= f
+
+if __name__ == '__main__':
+    n, m = 2, 15
+    print('First %i members of fractran(%i):\n  ' % (m, n) +
+          ', '.join(str(f) for f,i in zip(fractran(n), range(m))))

Task/Fractran/Python/fractran-2.py

@@ -0,0 +1,13 @@
+from fractran import fractran
+
+def fractran_primes():
+    for i, fr in enumerate(fractran(2), 1):
+        binstr = bin(fr)[2:]
+        if binstr.count('1') == 1:
+            prime = binstr.count('0')
+            if prime > 1:   # Skip 2**0 and 2**1
+                yield prime, i
+
+if __name__ == '__main__':
+    for (prime, i), j in zip(fractran_primes(), range(15)):
+        print("Generated prime %2i from the %6i'th member of the fractran series" % (prime, i))