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%I #16 Sep 28 2022 13:52:10
%S 4,0,5,2,8,4,7,3,4,5,6,9,3,5,1,0,8,5,7,7,5,5,1,7,8,5,2,8,3,8,9,1,0,5,
%T 5,5,6,1,7,4,3,5,0,9,8,6,8,8,9,8,6,1,9,5,3,8,2,4,3,6,1,2,7,5,7,6,6,9,
%U 2,4,8,3,8,4,8,9,4,1,7,6,4,7,6,4,8,3,7,0,9,5,7,0,2,4,8,7,3,5,0
%N Decimal expansion of 4/Pi^2.
%C Density of the odd squarefree numbers A056911. - _Charles R Greathouse IV_, Jun 08 2016
%D C. F. Gauss, Disquisitiones Arithmeticae, Yale, 1965; see p. 359.
%H G. C. Greubel, <a href="/A185199/b185199.txt">Table of n, a(n) for n = 0..5000</a>
%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%e 0.40528473456935108577551785283891055561743509868898619538243...
%t RealDigits[4/Pi^2, 10, 50][[1]] (* _G. C. Greubel_, Jun 24 2017 *)
%o (PARI) 4/Pi^2 \\ _Charles R Greathouse IV_, Jun 08 2016
%K cons,nonn
%O 0,1
%A _N. J. A. Sloane_, Feb 19 2011