Problem 58013. Find a number m such that 2m and the square of m have the same digit sum
The number
has the property that
and
have the same digit sum. It is the seventh number, including zero, in the sequence of numbers with that property.
Write a function to find the nth term in the sequence, where n can be a vector.
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2 Comments
Christian Schröder
on 23 Apr 2023
> It is the sixth number, including zero, in the sequence of numbers with that property.
Isn't it the seventh?
Also, out of curiosity, why are you disallowing persistent variables?
ChrisR
on 23 Apr 2023
Yes, seventh--corrected, thanks. Bitten by the "off by one bug" again.
Banning persistent is to add the challenge of dealing with large numbers in Cody time. A while ago I found a quicker way to find the digit sums of a lot of numbers, and this problem was another place to exploit that method.
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