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 A091925 Decimal expansion of Pi^3. 26
 3, 1, 0, 0, 6, 2, 7, 6, 6, 8, 0, 2, 9, 9, 8, 2, 0, 1, 7, 5, 4, 7, 6, 3, 1, 5, 0, 6, 7, 1, 0, 1, 3, 9, 5, 2, 0, 2, 2, 2, 5, 2, 8, 8, 5, 6, 5, 8, 8, 5, 1, 0, 7, 6, 9, 4, 1, 4, 4, 5, 3, 8, 1, 0, 3, 8, 0, 6, 3, 9, 4, 9, 1, 7, 4, 6, 5, 7, 0, 6, 0, 3, 7, 5, 6, 6, 7, 0, 1, 0, 3, 2, 6, 0, 2, 8, 8, 6, 1, 9 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Surface area of the 6-dimensional unit sphere. - Stanislav Sykora, Nov 08 2013 Surface area of a sphere of diameter Pi equals the volume of the circumscribed cube. - Omar E. Pol, Dec 25 2013 Area of a circle of radius Pi. - Omar E. Pol, Jan 31 2016 LINKS Harry J. Smith, Table of n, a(n) for n = 2..20000 G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 31 Khodabakhsh Hessami Pilehrood, Tatiana Hessami Pilehrood, Series acceleration formulas for beta values, Discrete Mathematics & Theoretical Computer Science 12:2 (2010), pp. 223-236. S. Sykora, Surface Integrals over n-Dimensional Spheres FORMULA Sum_{k >= 0} binomial(2*k,k)/((2*k + 1)^3*16^k) = 7*Pi^3/216. (Kh. Hessami Pilehrood and T. Hessami Pilehrood). From Peter Bala, Feb 05 2015: (Start) The integer sequences A(n) := 2^n*(2*n + 1)!^3/n!^2 and B(n) := A(n)*( Sum {k = 0..n} binomial(2*k,k)*1/(2*k + 1)^3*(1/16)^k ) both satisfy the second order recurrence equation u(n) = (160*n^4 + 128*n^3 + 144*n^2 + 2)*u(n-1) - 32*(n - 1)*(2*n - 1)^7*u(n-2). From this observation we can obtain the continued fraction expansion 7/216*Pi^3 = 1 + 2/(432 - 32*3^7/(4162 - 32*2*5^7/(17714 - ... - 32*(n - 1)*(2*n - 1)^7/((160*n^4 + 128*n^3 + 144*n^2 + 2) - ... )))). Cf. A002388, A019670 and A093954. (End) EXAMPLE 31.00627668029982017547631506710139520222528856588510769414453810380639... MATHEMATICA First@ RealDigits@ N[Pi^3, 120] (* Michael De Vlieger, Jan 31 2016 *) PROG (PARI) default(realprecision, 20080); x=Pi^3/10; for (n=2, 20000, d=floor(x); x=(x-d)*10; write("b091925.txt", n, " ", d)); \\ Harry J. Smith, Jun 22 2009 (MAGMA) R:= RealField(100); (Pi(R))^3; // G. C. Greubel, Mar 09 2018 CROSSREFS Cf. A000796, A002388, A058285 (continued fraction), A019670, A093954. Sequence in context: A112295 A318973 A110517 * A034370 A144402 A264429 Adjacent sequences:  A091922 A091923 A091924 * A091926 A091927 A091928 KEYWORD easy,nonn,cons AUTHOR Mohammad K. Azarian, Mar 16 2004 STATUS approved

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Last modified October 15 22:25 EDT 2019. Contains 328038 sequences. (Running on oeis4.)