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%I #17 Jun 18 2021 09:04:07
%S 6,18,55,174,548,1733,5478,17321,54773,173206,547723,1732051,5477226,
%T 17320509,54772256,173205081,547722558,1732050808,5477225576,
%U 17320508076,54772255751,173205080757,547722557506,1732050807569,5477225575052,17320508075689,54772255750517
%N a(n) is root of square starting with digit 3: first term of runs.
%H Michael S. Branicky, <a href="/A035070/b035070.txt">Table of n, a(n) for n = 1..1999</a>
%F a(n) = ceiling(sqrt(3*10^n)).
%t Table[Ceiling @ Sqrt[3 * 10^n], {n, 1, 24}] (* _Amiram Eldar_, Oct 08 2019 *)
%o (Python)
%o from math import isqrt
%o def a(n): return isqrt(3*10**n) + 1
%o print([a(n) for n in range(1, 28)]) # _Michael S. Branicky_, Jun 18 2021
%Y Cf. A067473 (squares), A035076 (2..9).
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Nov 15 1998
%E Offset 1 from _Alois P. Heinz_, Oct 08 2019