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%I #16 Jan 28 2024 16:57:31
%S 9,339889,3383399889,3398339883988899839889,39989983893893399999889
%N Squares composed of digits {3,8,9}.
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/threedigits.htm">Index to related sequences</a>
%H Hisanori Mishima, <a href="http://www.asahi-net.or.jp/~KC2H-MSM/mathland/math02/math0210.htm#389">Sporadic tridigital solutions</a>
%t Select[Flatten[Table[10#+9&/@FromDigits/@Tuples[{3,8,9},n],{n,0,10}]],IntegerQ[Sqrt[#]]&] (* The program generates the first three terms of the sequence. *) (* _Harvey P. Dale_, Jan 28 2024 *)
%Y Cf. A058467.
%K nonn,base,hard,more
%O 1,1
%A _Patrick De Geest_, Nov 15 2000
%E a(3) corrected by _Sascha Kurz_, Jun 12 2021