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Odd digited square (Posted on 2019-06-02)

Find all natural numbers n such that n² has only odd digits.

No Solution Yet Submitted by Danish Ahmed Khan

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Comment 8 of 8 |

It can be shown that there does NOT exist any positive integer n such that we cannot have n^2 having more than 1 digit.

Thus n^2 must have precisely 1 digit.

We know that

n=1 gives n^2=1

n=3 gives n^2=9

Consequently, the required values of n are 1 and 3.

Posted by K Sengupta on 2022-06-09 00:33:00

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