Data commit

Task/Numbers-with-equal-rises-and-falls/Python/numbers-with-equal-rises-and-falls.py

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+import itertools
+
+def riseEqFall(num):
+    """Check whether a number belongs to sequence A296712."""
+    height = 0
+    d1 = num % 10
+    num //= 10
+    while num:
+        d2 = num % 10
+        height += (d1<d2) - (d1>d2)
+        d1 = d2
+        num //= 10
+    return height == 0
+
+def sequence(start, fn):
+    """Generate a sequence defined by a function"""
+    num=start-1
+    while True:
+        num += 1
+        while not fn(num): num += 1
+        yield num
+
+a296712 = sequence(1, riseEqFall)
+
+# Generate the first 200 numbers
+print("The first 200 numbers are:")
+print(*itertools.islice(a296712, 200))
+
+# Generate the 10,000,000th number
+print("The 10,000,000th number is:")
+print(*itertools.islice(a296712, 10000000-200-1, 10000000-200))
+# It is necessary to subtract 200 from the index, because 200 numbers
+# have already been consumed.