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%I #29 Jul 04 2023 11:10:35
%S 2,2,4,3,0,2,8,5,8,0,2,8,7,6,0,2,5,7,0,1,2,7,8,0,2,1,9,2,8,2,9,0,6,6,
%T 5,4,0,5,0,8,9,7,3,1,4,2,4,0,6,6,0,9,9,7,5,9,1,8,8,2,3,7,0,1,3,8,7,4,
%U 0,4,8,0,4,2,2,8,9,9,9,5,7,2,2,4,1,1,1,5,0,5,9,0,9,4,1,9,5,0,2,1,8,5
%N Decimal expansion of agm(1,4), the arithmetic-geometric mean of 1 and 4.
%H Ivan Panchenko, <a href="/A084896/b084896.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Arithmetic-GeometricMean.html">Arithmetic-Geometric Mean</a>
%F 2.2430285802876025701278021928290665405089731424066099759188237013874048...
%t RealDigits[ArithmeticGeometricMean[1,4],10,120][[1]] (* _Harvey P. Dale_, May 25 2014 *)
%t RealDigits[N[5Pi/(4EllipticK[9/25]), 102]][[1]] (* _Jean-François Alcover_, Jun 02 2019 *)
%o (PARI) agm(1, 4) \\ _Michel Marcus_, Jun 02 2019
%Y Cf. A068521 (agm(1,2)), A084895 (agm(1,3)), A084897 (agm(1,5)).
%K nonn,cons,easy
%O 1,1
%A _Eric W. Weisstein_, Jun 10 2003