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%I #44 Jan 12 2025 10:50:45
%S 3,1,4,1,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
%T 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
%U 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6
%N Decimal expansion of 377/120.
%C Claudius Ptolemy's estimate for Pi.
%D Petr Beckmann, A History of Pi, 3rd Ed., Boulder, Colorado: The Golem Press (1974): p. 26.
%D Jan Gullberg, Mathematics from the Birth of Numbers, W. W. Norton & Co., NY & London, 1997, §3.6 The Quest for Pi, p. 90.
%D David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 49.
%H Dario Castellanos, <a href="http://www.jstor.org/stable/2690037">The ubiquitous Pi</a>, Math. Mag., 61 (1988), pp. 67-98 and pp. 148-163.
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F Equals A021028 plus 3.1. - _R. J. Mathar_, Mar 27 2012
%F Equals 3 + A122553 + A021016/10. - _Stefano Spezia_, Jul 08 2022
%F From _Elmo R. Oliveira_, Aug 02 2024: (Start)
%F G.f.: x*(3 + x + 4*x^2 + x^3) + 6*x^5/(1 - x).
%F a(n) = 6 for n >= 5. (End)
%e 3.1416666666666666666666666666666666666666666666666666666666...
%t RealDigits[377/120,10,120][[1]] (* or *) PadRight[{3,1,4,1},120,{6}] (* _Harvey P. Dale_, Dec 06 2017 *)
%o (PARI) 377/120. \\ _Charles R Greathouse IV_, Mar 25 2014
%Y Cf. A021016, A021028, A122553.
%K nonn,cons,easy,changed
%O 1,1
%A _N. J. A. Sloane_, Mar 24 2012