Solution

(related to Problem: Digital Square Numbers)

So far as I know, there are no published tables of square numbers that go sufficiently high to be available for the purposes of this puzzle. The lowest square number containing all the nine digits once, and once only, is $139,854,276,$ the square of $11,826.$ The highest square number under the same conditions is, $923,187,456,$ the square of $30,384.$


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References

Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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