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Numbers k such that k^2 contains only digits {3,4,7}.
1

%I #12 Mar 10 2024 09:17:43

%S 2,88,688,8564136525847038,21150351639576462,20913496712251033188,

%T 1864878916830083039312,271006150065722262703289312

%N Numbers k such that k^2 contains only digits {3,4,7}.

%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#347">Sporadic tridigital solutions</a>

%Y Cf. A058464.

%K nonn,base,hard,more

%O 1,1

%A _Patrick De Geest_, Nov 15 2000

%E More terms from Mishima's webpage added by _Max Alekseyev_, May 30 2009

%E a(8) from _Zhao Hui Du_, Mar 10 2024