September Morn Update

Task/Fibonacci-sequence/Python/fibonacci-sequence-14.py

@@ -0,0 +1,31 @@
+'''Fibonacci accumulation'''
+
+from itertools import (accumulate, chain)
+
+
+# fibs :: Integer :: [Integer]
+def fibs(n):
+    '''An accumulation of the first n integers in
+       the Fibonacci series. The accumulator is a
+       pair of the two preceding numbers.
+    '''
+    def go(ab, _):
+        a, b = ab
+        return (b, a + b)
+
+    return [xy[1] for xy in accumulate(
+        chain(
+            [(0, 1)],
+            range(1, n)
+        ),
+        go
+    )]
+
+
+# MAIN ---
+if __name__ == '__main__':
+    print(
+        'First twenty: ' + repr(
+            fibs(20)
+        )
+    )

Task/Fibonacci-sequence/Python/fibonacci-sequence-15.py

@@ -0,0 +1,21 @@
+'''Nth Fibonacci term (by folding)'''
+
+from functools import (reduce)
+
+
+# nthFib :: Integer -> Integer
+def nthFib(n):
+    '''Nth integer in the Fibonacci series.'''
+    def go(ab, _):
+        a, b = ab
+        return (b, a + b)
+    return reduce(go, range(1, n), (0, 1))[1]
+
+
+# MAIN ---
+if __name__ == '__main__':
+    print(
+        '1000th term: ' + repr(
+            nthFib(1000)
+        )
+    )