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%I #16 Jul 27 2018 08:46:14
%S 5,75,235,745,22485,22925,235065,505525,2356384,23569166,227069495,
%T 674919666,3931354166,7450205075,39969432765,524933839166,
%U 2134374738666,4904646324166,23802428354166
%N a(n)^2 is the smallest square containing exactly n 5's.
%C a(20) > 10^14. - _Giovanni Resta_, Jul 27 2018
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number</a>
%t k := 1; For[n = 1, n < 30000, n++, If[DigitCount[n^2][[5]] == k, k++; Print[n]]] (* _Stefan Steinerberger_, Apr 09 2006 *)
%t a[n_] := Module[{i = 1}, While[DigitCount[i^2][[6]] != n, i++;]; i]; (* Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 20 2006 *)
%Y Cf. A036512, A034986, A048351.
%K nonn,base,more
%O 1,1
%A _Patrick De Geest_, Mar 15 1999
%E More terms from _Jon E. Schoenfield_, Jan 14 2009
%E One more term from _Jon E. Schoenfield_, Jan 25 2009
%E a(17)-a(19) from _Giovanni Resta_, Jul 27 2018
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