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%I #25 Feb 29 2024 09:16:50
%S 5,15,235,485,1885,5765,15885,50235,57665,72335,1798765,15249765,
%T 187703365,179876492415,159789024443333515,576387476638096486959455635
%N Numbers k such that k^2 contains only digits {2,3,5}.
%H Michael S. Branicky, <a href="/A053918/a053918.txt">Python program</a>
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/threedigits.htm">Squares containing at most three distinct digits, Index entries for related sequences</a>
%H Author?, <a href="http://web.archive.org/web/20080708203024/http://blue.kakiko.com/mmrmmr/htm/eqtn06.html">Source</a>(<a href="http://web.archive.org/web/20060426155831/http://blue.kakiko.com/mmrmmr/txt/eqtn06.txt">txt</a>)
%H H. Mishima <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#235">Squares consisted of 3 different digits</a>
%o (Python) # see link for faster version
%o def aupto(limit):
%o alst = []
%o for k in range(1, limit+1):
%o if set(str(k*k)) <= set("235"): alst.append(k)
%o return alst
%o print(aupto(2*10**6)) # _Michael S. Branicky_, May 15 2021
%Y Cf. A053919.
%K nonn,base,more
%O 1,1
%A _Patrick De Geest_, Mar 15 2000
%E More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005
%E One more term from Mishima's webpage added by _Max Alekseyev_, Jun 17 2011
%E a(16) from _Zhao Hui Du_, Feb 29 2024