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%I #27 Apr 12 2024 18:14:39
%S 2,5,235,2335,23335,233335,2333335,2354235,23333335,233333335,
%T 2333333335,2333524235,23333333335,23333524235,233333333335,
%U 2333333333335,23333333333335,233333333333335,2333333333333335,23333333333333335,233333333333333335
%N Numbers k such that k and k^2 use only the digits 2, 3, 4 and 5.
%C Generated with DrScheme.
%C Contains 2*10^m + (10^m-1)/3 + 2 for m >= 2. Are these all the terms > 23333524235? There are no others with up to 25 digits. - _Robert Israel_, Jul 02 2018
%C There are no others than those of that form with up to 35 digits. - _Michael S. Branicky_, May 25 2021
%H Jonathan Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived].
%e 23333524235^2 = 544453353225332335225.
%o (PARI) isokd(x) = (x < 2) || (x > 5);
%o isok(n) = !#select(x->isokd(x), digits(n)) && !#select(x->isokd(x), digits(n^2)); \\ _Michel Marcus_, Jul 02 2018
%o (Python) # uses auptod in A137110
%o print(auptod(16, only="2345")) # _Michael S. Branicky_, May 25 2021
%Y Cf. A137110.
%K base,nonn,changed
%O 1,1
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008
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