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%I #20 Sep 08 2022 08:45:23
%S 4,676,69696,6996025,699972849,69999930625,6999998354001,
%T 699999994145169,69999999943667161,6999999999658218721,
%U 699999999965821872100,69999999999757088783236,6999999999996874888812096,699999999999952064012316025,69999999999999968753591518681
%N a(n) = floor(sqrt(7) * 10^n)^2.
%C Largest square less than 7 * 10^(2n).
%H Andrew Howroyd, <a href="/A114765/b114765.txt">Table of n, a(n) for n = 0..100</a>
%e sqrt(7) = 2.645751311...
%e floor(sqrt(7) * 10) = 26 and 26^2 = 676, so a(1) = 676.
%e floor(sqrt(7) * 100) = 264 and 264^2 = 69696, so a(2) = 69696.
%e floor(sqrt(7) * 1000) = 2645 and 2645^2 = 6996025, so a(3) = 6996025.
%t $MaxExtraPrecision := 200; Table[Floor[7^(1/2) * 10^n]^2, {n, 0, 20}] (* _Stefan Steinerberger_, Jan 26 2006 *)
%o (Magma) [Floor(7^(1/2)*10^n)^2: n in [0..150]]; // _Vincenzo Librandi_, Feb 05 2011
%o (PARI) a(n)={sqrtint(7*10^(2*n))^2} \\ _Andrew Howroyd_, Nov 09 2019
%Y Cf. A114761, A114762, A114763, A114764.
%Y Cf. A010465 (sqrt(7)).
%K nonn
%O 0,1
%A _Amarnath Murthy_, Nov 17 2005
%E More terms from _Stefan Steinerberger_, Jan 26 2006
%E Terms a(12) and beyond from _Andrew Howroyd_, Nov 09 2019
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