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%I #20 Jun 21 2018 05:30:22
%S 7,2,5,6,9,4,6,4,0,4,8,6,0,5,7,6,7,8,0,1,3,2,8,3,8,3,8,8,6,9,0,7,6,9,
%T 2,3,6,6,1,9,0,1,7,2,3,7,1,8,3,2,1,4,8,5,7,5,0,9,8,7,9,6,7,8,7,7,7,1,
%U 0,9,3,4,6,7,3,6,8,2,0,2,7,2,8,1,7,7,2,0,2,3,8,4,8,9,7,9,2,4,6,9,2,6
%N Consider surface area of unit sphere as a function of the dimension d; maximize this as a function of d (considered as a continuous variable); sequence gives decimal expansion of the best d.
%D N. Cakic, D. Letic, B. Davidovic, The Hyperspherical functions of a derivative, Abstr. Appl. Anal. (2010) 364292 doi:10.1155/2010/364292
%H Dusko Letic, Nenad Cakic, Branko Davidovic and Ivana Berkovic, <a href="http://www.advancesindifferenceequations.com/content/2012/1/22">Orthogonal and diagonal dimension fluxes of hyperspherical function</a>, Advances in Difference Equations 2012, 2012:22. - From _N. J. A. Sloane_, Sep 04 2012
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Hypersphere.html">Hypersphere</a>
%F Equals 2 + A074455.
%e 7.2569464048605767801328383886907692366190172371832148575098796787771093\
%e 4673682027281772023848979246926957...
%t RealDigits[ FindMinimum[ -n*Pi^(n/2)/(n/2)!, {n, 7}, WorkingPrecision -> 125] [[2, 1, 2]]] [[1]]
%t x /. FindRoot[ PolyGamma[x/2] == Log[Pi], {x, 7}, WorkingPrecision -> 105] // RealDigits // First (* _Jean-François Alcover_, Mar 28 2013 *)
%Y Surface area is A074456. Cf. A072478 & A072479.
%K cons,nonn
%O 1,1
%A _Robert G. Wilson v_, Aug 22 2002
%E Corrected by _Eric W. Weisstein_, Aug 31 2003
%E Corrected by _Martin Fuller_, Jul 12 2007
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