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%I #13 Mar 09 2024 18:29:03
%S 1,4,9,41,109,1291,28604,78541,81619,782104,1054119,3341881,4345881,
%T 25823791,29439546,129105041,817851954,931064546,2486185454,
%U 2609955204,24862847104,786680914454
%N Numbers k such that k^2 contains only digits {1,6,8}.
%H Zhao Hui Du, <a href="/A053908/b053908.txt">Table of n, a(n) for n = 1..27</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>
%Y Cf. A053909.
%K nonn,base
%O 1,2
%A _Patrick De Geest_, Mar 15 2000
%E More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 04 2005