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%I #15 Sep 08 2022 08:45:49
%S 2,2,6,9,1,8,5,3,1,4,2,1,3,0,2,1,9,6,8,1,1,4,4,9,0,8,1,0,3,0,6,5,7,2,
%T 4,7,5,7,2,5,9,8,1,5,8,5,5,0,4,0,0,1,3,5,0,0,5,0,6,5,8,2,2,2,3,6,0,2,
%U 7,8,6,5,5,7,9,3,7,6,8,8,2,0,7,6,5,4,4,3,5,4,9,1,0,1,2,5,1,8,9
%N Decimal expansion of 2/log(1+sqrt(2)).
%C Critical temperature for two-dimensional Ising model.
%H G. C. Greubel, <a href="/A169800/b169800.txt">Table of n, a(n) for n = 1..10000</a>
%H M. Richey, <a href="http://www.jstor.org/stable/10.4169/000298910x485923">The evolution of Markov chain Monte Carlo Methods</a>, Amer. Math. Monthly, 117 (No. 5, 2010), 383-413.
%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%e 2.2691853142130219681144908103065724757259815855040013500506...
%t RealDigits[2/Log[1 + Sqrt[2]], 10, 100][[1]] (* _G. C. Greubel_, Oct 02 2018 *)
%o (PARI) 2/log(1+sqrt(2)) \\ _Charles R Greathouse IV_, Mar 25 2014
%o (Magma) SetDefaultRealField(RealField(100)); 2/Log(1+Sqrt(2)); // _G. C. Greubel_, Oct 02 2018
%Y Cf. A091648 (log(1 + sqrt(2))).
%K nonn,cons
%O 1,1
%A _N. J. A. Sloane_, May 18 2010