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%I #11 Apr 12 2024 09:51:27
%S 2,8,22,68,92,222,262,264,288,668,964,6668,6962,9288,9842,26262,49462,
%T 49692,49842,66668,69462,82864,99462,99842,494262,494462,499462,
%U 649842,666668,684462,984288,999462,4944662,4946662,4989886,4994622,4994662,4996886,4996962,4998268,6666668,6994462,6999462,8284262,9469262,9994622,29482622,49294288
%N Numbers k such that k and k^2 use only the digits 2, 4, 6, 8 and 9.
%C Generated with DrScheme.
%H Jonathan Wellons, <a href="/A137104/b137104.txt">Table of n, a(n) for n = 1..497</a>
%H J. Wellons, <a href="https://web.archive.org/web/20090206165028/http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a> [archived]
%e 984829269296292^2 = 969888689662668428628884949264.
%t With[{c={2,4,6,8,9}},Flatten[Table[Select[FromDigits/@Tuples[ c,n], SubsetQ[ c,IntegerDigits[ #^2]]&],{n,8}]]] (* The program uses the SubsetQ function from Mathematica version 10 *) (* _Harvey P. Dale_, Nov 15 2014 *)
%K base,nonn
%O 1,1
%A Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008