%I
%S 1,81,2025,9,20736,324,36,1296,5184,1,9801,81,680625,2509056,
%T 160579584,4356,3828515625,37387847900390625,3025,164433494016,245025,
%U 680625,2025,95712890625,17015625,156816,627264,1936,40144896,59820556640625
%N Smallest natural number k such that periodic part of 1/sqrt(k) is n (or 0 if no such number).
%C I believe a(n) = 0 will eventually occur (see A037207).
%C The smallest n such that A037207(n) = 0 is n = 101, so the smallest n such that a(n) = 0 is n = 101 as well.  _Jianing Song_, Feb 06 2019
%F a(n) = A037207(n)^2.  _Henry Bottomley_
%e 1/sqrt(20736) = 0.0069444444444444444444; a(4) = 20736.
%Y Cf. A037207.
%K nonn,base,nice
%O 0,2
%A _N. J. A. Sloane_
%E More terms from _Henry Bottomley_, Apr 28 2000
