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%I #21 Mar 04 2024 11:55:35
%S 3,173,264,964,3114,31563,163187,264437,16431563,96032404423,
%T 99647694036,9813067816077,51665201022187,51960847753114,
%U 7935361806302386,78883604126137785577,47567102808870567435673,26395073915340646948470264
%N Numbers k such that k^2 contains only digits {2,6,9}.
%H Joe K. Crump, <a href="http://web.archive.org/web/20100308181731/http://www.immortaltheory.com/NumberTheory/TriDigitalSquares.htm">TriDigital Squares</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>
%o (PARI) isok(n) = {digs = digits(n^2); for (i = 1, #digs, if ((digs[i] != 2) && (digs[i] != 6) && (digs[i] != 9), return (0));); return (1);} \\ _Michel Marcus_, Sep 02 2013
%Y Cf. A053931.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Mar 15 2000
%E More terms from Joe K. Crump (joecr(AT)carolina.rr.com), Sep 07 2000
%E a(17)-a(19) from _Zhao Hui Du_, Mar 01 2024
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