This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A210621 #50 Mar 18 2025 21:41:05 %S A210621 3,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3, %T A210621 8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4, %U A210621 9,3,8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3,8,2,7,1,6,0,4,9,3,8,2 %N A210621 Decimal expansion of 256/81. %C A210621 According to Maor (1994), the Rhind Papyrus asserts that a circle has the same area as a square with a side that is 8/9 the diameter of the circle. From this we can determine that 256/81 is one of the ancient Egyptian approximations of Pi. - _Alonso del Arte_, Jun 12 2012 %D A210621 Petr Beckmann, A History of Pi, 3rd Ed., Boulder, Colorado: The Golem Press (1974): p. 12. %D A210621 Calvin C. Clawson, Mathematical Mysteries, The Beauty and Magic of Numbers, Perseus Books, 1996, p. 88. %D A210621 John H. Conway and Richard K. Guy, The Book of Numbers, New York: Springer-Verlag, 1996. See p. 237. %D A210621 Jan Gullberg, Mathematics from the Birth of Numbers, W. W. Norton & Co., NY & London, 1997, ยง3.6 The Quest for Pi, p. 89. %D A210621 Carl Theodore Heisel, Behold! The grand problem no longer unsolved: The circle squared beyond refutation, c. 1935. (proposes Pi = 3 + 13/81) %D A210621 Eli Maor, e: The Story of a Number. Princeton, New Jersey: Princeton University Press (1994): 41, 47 note 1. %D A210621 David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 48. %H A210621 Dario Castellanos, <a href="http://www.jstor.org/stable/2690037">The ubiquitous Pi</a>, Math. Mag., 61 (1988), 67-98 and 148-163. %H A210621 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,1). %F A210621 256/81 = (4/3)^4. %F A210621 Equals 3*A229943 = A255910^2 = A268315/3. - _Hugo Pfoertner_, Jun 26 2024 %e A210621 3.1604938271604938271604938271604938271604938271604938271604... %t A210621 RealDigits[256/81, 10, 100][[1]] (* _Alonso del Arte_, Jun 12 2012 *) %o A210621 (PARI) 256/81. \\ _Charles R Greathouse IV_, Sep 13 2013 %Y A210621 Cf. A068028, A229943, A255910, A268315. %K A210621 nonn,cons,easy %O A210621 1,1 %A A210621 _N. J. A. Sloane_, Mar 24 2012 %E A210621 Offset corrected by _Rick L. Shepherd_, Jan 06 2014