More powers of 3

Following the discovery of a question to which the answer is 42, the same team has now reported a sum of three cubes equal to 3.  As before, the result can be checked from Excel, linking to mpmath, via pyxll.

In the first example each of the three cubes is evaluated, and the resulting strings are concatenated into a single string function that is evaluated:

The mp-Eval function also allows values to be assigned to symbols, which can then be evaluated.  In this example the letters a to d are replaced with the values in the cells to the right, and substituted into the function in cell A41:

Using the same approach, a rather simpler solution to the problem can be found:

Further discussion of the background to this problem can be found at The Math Less Travelled, which has links to on-line calculators to solve the problem summing to 42, and it is also pointed out that that the formula can be evaluated directly in Python:

Also worth a read is the Wikipedia article on the sum of three cubes, which contains further examples and numerous links.

This entry was posted in Computing - general, Excel, Link to Python, Maths, Newton, PyXLL and tagged , , , , , . Bookmark the permalink.

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