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%I #8 Aug 29 2024 02:39:44
%S 1,10,105,1054,10540,105409,1054092,10540925,105409255,1054092553,
%T 10540925533,105409255338,1054092553389,10540925533894,
%U 105409255338945,1054092553389459,10540925533894597,105409255338945977
%N Integer part of the square root of (2n-1)-th decimal repunit.
%F a(n) = floor(sqrt((10^(2*n-1)-1)/9)).
%F a(n) = A000196(A002275(2*n-1)).
%F a(n) = A096483(2*n-1). - _Jason Yuen_, Aug 29 2024
%e a(4) = floor(sqrt(1111111)) = 1054. 1111111 is the 7th decimal repunit.
%Y Cf. A000196, A002275, A096483.
%K base,nonn,easy
%O 1,2
%A _Labos Elemer_, Jun 24 2004