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Singular Cubes (Posted on 2022-07-19)

What is the largest (positive) perfect cube whose digits are in strictly ascending order from left to right?
The same in strictly descending order?

See The Solution Submitted by K Sengupta

Rating: 4.0000 (1 votes)

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Solution

Comment 1 of 1

Curiously, the largest perfect cube with strictly increasing digits is 125, and the largest with strictly decreasing digits is 64.

We don't have to test very many numbers.

The largest strictly ascending number is 123456789 whose cube root is just under 498.

The largest strictly decreasing number is 9876543210 whose cube root is just under 2146.

Posted by Larry on 2022-07-19 09:23:36

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