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%I #15 Oct 01 2022 00:19:44
%S 3,5,6,8,2,4,8,2,3,2,3,0,5,5,4,2,2,2,9,0,7,7,9,3,2,7,4,5,1,3,0,1,6,5,
%T 1,8,0,7,8,8,4,0,5,8,4,1,1,4,3,9,0,6,9,4,3,7,1,8,5,4,7,6,9,1,6,9,1,0,
%U 6,1,5,5,9,0,6,0,8,6,1,5,5,0,5,1,9,6
%N Decimal expansion of sqrt(40/Pi).
%C A gauge point marked c^1 or c_1 ("c" with a superscripted or subscripted "1") on slide rule calculating devices in the 20th century. The Pickworth reference notes its use "in calculating the contents of cylinders".
%D C. N. Pickworth, The Slide Rule, 24th Ed., Pitman, London, 1945, p. 53, Gauge Points.
%H Peter Munn, <a href="/A337092/a337092.jpg">Aristo 89 Slide Rule</a>
%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%F Equals A010494/A002161 = 2*sqrt(10*A049541).
%e 3.568248232305...
%p evalf(sqrt(40.0/Pi)) ; # _R. J. Mathar_, Sep 02 2020
%t RealDigits[Sqrt[40/Pi], 10, 100][[1]] (* _Amiram Eldar_, Aug 15 2020 *)
%o (PARI) sqrt(40/Pi) \\ _Michel Marcus_, Aug 19 2020
%Y Cf. A002161, A010494, A190732.
%K nonn,cons
%O 1,1
%A _Peter Munn_, Aug 15 2020