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%I #23 Mar 31 2018 16:55:54
%S 3,4,9,6,0,7,6,7,3,9,0,5,6,1,5,9,7,4,7,2,8,6,4,5,2,7,8,6,5,2,1,4,9,2,
%T 5,5,1,5,7,7,0,0,6,6,0,1,9,0,8,8,3,0,8,8,3,7,5,5,7,6,2,2,7,1,7,3,4,3,
%U 8,7,4,4,9,4,2,7,2,1,9,0,0,0,3,0,7,0,6,0,7,1,0,6,1,5,2,3,8,7,9,1
%N Decimal expansion of the area of the quartic curve with implicit Cartesian equation x^4 + y^2 = 1 (sometimes called "elliptic lemniscate").
%H G. C. Greubel, <a href="/A227717/b227717.txt">Table of n, a(n) for n = 1..10000</a>
%H Serge Mehl, <a href="http://serge.mehl.free.fr/anx/lemniEll.html">Lemniscate elliptique</a> [in French].
%F Equals 4*Integral_{0..1} sqrt(1 - x^4).
%F Equals sqrt(Pi)*Gamma(1/4)/(2*Gamma(7/4)).
%F Equals 1/3*sqrt(2/Pi)*Gamma(1/4)^2. - _Vaclav Kotesovec_, Jul 26 2013
%e 3.4960767390561597472864527865214925515770066019088308837557622717343874494272...
%t Sqrt[Pi]*Gamma[1/4]/(2*Gamma[7/4]) // RealDigits[#, 10, 100]& // First
%o (PARI) sqrt(2/Pi)*gamma(1/4)^2/3 \\ _Michel Marcus_, Jul 04 2015
%Y Cf. A227718 (length).
%K nonn,cons
%O 1,1
%A _Jean-François Alcover_, Jul 22 2013
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