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%I
%S 2,2,3,7,3,5,1,9,4,3,1,3,7,6,0,1,2,2,4,5,9,6,8,4,1,0,9,6,7,8,4,8,9,8,
%T 0,6,6,2,2,8,8,5,1,8,8,6,9,3,8,8,8,2,5,5,5,3,8,2,4,9,9,1,8,3,7,8,0,5,
%U 1,4,5,6,6,1,7,2,6,5,3,1,6,8,2,6,9,6,6,8,2,1,3,4,6,9,4,9,4,8,0,0,2,8,0,4,5
%N Decimal expansion of 3344161/1494696.
%C 3344161/1494696 is a rational number r such that both r^2 + 5 and r^2 - 5 are the squares of rational numbers because r^2 + 5 = (4728001/1494696)^2 and r^2 - 5 = (113279/1494696)^2.
%C 2, 2, 3, 7 followed by repetitions of a period 210 sequence.
%D J. Svoboda, L'intermédiaire des math., 21, 1914, pp. 176-178.
%H Arkadiusz Wesolowski, <a href="/A208151/b208151.txt">Table of n, a(n) for n = 1..1000</a>
%H Alessandro Padoa, <a href="https://www.mathunion.org/fileadmin/ICM/Proceedings/ICM1928.2/ICM1928.2.ocr.pdf">Un duplice sistema indeterminato</a>, Atti del Congresso Internazionale dei Matematici Bologna 3-10 Settembre 1928 (VI) Tomo II, Comunicazioni Sezione I (A-B), pp. 25-30.
%e 3344161/1494696 = 2.237351943137601224596841096....
%t RealDigits[N[3344161/1494696, 200]][[1]]
%o (PARI) default(realprecision, 200); x=3344161/1494696; for(n=1, 200, d=floor(x); x=(x-d)*10; print1(d, ", "));
%K cons,easy,nonn
%O 1,1
%A _Arkadiusz Wesolowski_, Feb 27 2012
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