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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.

A289265 Decimal expansion of the real root of x^3 - x^2 - 2 = 0.

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%I A289265 #31 Feb 11 2025 14:23:33
%S A289265 1,6,9,5,6,2,0,7,6,9,5,5,9,8,6,2,0,5,7,4,1,6,3,6,7,1,0,0,1,1,7,5,3,5,
%T A289265 3,4,2,6,1,8,1,7,9,3,8,8,2,0,8,5,0,7,7,3,0,2,2,1,8,7,0,7,2,8,4,4,5,2,
%U A289265 4,4,5,3,4,5,4,0,8,0,0,7,2,2,1,3,9,9
%N A289265 Decimal expansion of the real root of x^3 - x^2 - 2 = 0.
%D A289265 D. E. Daykin and S. J. Tucker, Introduction to Dragon Curves, unpublished, 1976, end of section 2.  See links in A003229.
%H A289265 Angel Chang and Tianrong Zhang, <a href="http://www.coiraweb.com/poignance/math/Fractals/Dragon/Bound.html">The Fractal Geometry of the Boundary of Dragon Curves</a>, Journal of Recreational Mathematics, volume 30, number 1, 1999-2000, pages 9-22.
%H A289265 <a href="/index/Al#algebraic_03">Index entries for algebraic numbers, degree 3</a>.
%F A289265 r = D^(1/3) + (1/9)*D^(-1/3) + 1/3 where D = 28/27 + (1/9)*sqrt(29*3) [Chang and Zhang] from the usual cubic solution formula.  Or similarly r = (1/3)*(1 + C + 1/C) where C = (28 + sqrt(29*27))^(1/3). - _Kevin Ryde_, Oct 25 2019
%e A289265 1.6956207695598620574163671001175353426181793882085077...
%t A289265 z = 2000; r = 8/5;
%t A289265 u = CoefficientList[Series[1/Sum[Floor[(k + 1)*r] (-x)^k, {k, 0, z}], {x, 0, z}], x];  (* A289260 *)
%t A289265 v = N[u[[z]]/u[[z - 1]], 200]
%t A289265 RealDigits[v, 10][[1]] (* A289265 *)
%o A289265 (PARI) solve(x=1, 2, x^3 - x^2 - 2) \\ _Michel Marcus_, Oct 26 2019
%Y A289265 Sequences growing as this power: A003229, A003476, A003479, A052537, A077949, A144181, A164395, A164399, A164410, A164414, A164471, A203175, A227036, A289260, A292764.
%Y A289265 Cf. A078140 (includes guide to constants similar to A289260).
%K A289265 nonn,cons,easy
%O A289265 1,2
%A A289265 _Clark Kimberling_, Jul 14 2017