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%I #8 Nov 13 2017 19:51:27
%S 1,3,10,33,105,333,1054,3333,10540,33333,105409,333333,1054092,
%T 3333333,10540925,33333333,105409255,333333333,1054092553,3333333333,
%U 10540925533,33333333333,105409255338,333333333333,1054092553389
%N Integer part of the square root of n-th decimal repunit.
%H Robert Israel, <a href="/A096483/b096483.txt">Table of n, a(n) for n = 1..1998</a>
%F a[n]=Floor[sqrt[(-1+10^n)/9]].
%F If n is even, a(n) = (10^(n/2)-1)/3. - _Robert Israel_, Nov 13 2017
%p seq(floor(sqrt((10^n-1)/9)), n=1..100); # _Robert Israel_, Nov 13 2017
%t Floor[Sqrt[#]]&/@Table[FromDigits[PadRight[{},n,1]],{n,30}] (* _Harvey P. Dale_, Sep 24 2016 *)
%K base,nonn
%O 1,2
%A _Labos Elemer_, Jun 24 2004