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%I #11 Oct 03 2019 14:15:57
%S 0,1,2,42,61,88,238,254,288,347,575,4034,9853,21798,49736,108435,
%T 109003,181562,1035352,1955976,6950275,30712753,41463747,45117343,
%U 112401242,116579541
%N Increasing partial quotients of the continued fraction for agm(1,i)/(1+i).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Arithmetic-GeometricMean.html">Arithmetic-Geometric Mean</a>
%H Wolfram Research, <a href="http://functions.wolfram.com/EllipticFunctions/ArithmeticGeometricMean/">Arithmetic-Geometric Mean</a>
%e A076391(1) = 0
%e A076391(2) = 1
%e A076391(4) = 2
%e A076391(5) = 42
%e A076391(96) = 61
%e A076391(121) = 88
%e A076391(310) = 238
%e A076391(461) = 254
%e A076391(540) = 288
%e A076391(627) = 347
%e A076391(699) = 575
%e A076391(1136) = 4034
%e A076391(2986) = 9853
%e A076391(4172) = 21798
%e A076391(16727) = 49736
%e A076391(39201) = 108435
%e A076391(110180) = 109003
%e A076391(130606) = 181562
%e A076391(506314) = 1035352
%e A076391(512390) = 1955976
%e A076391(1248836) = 6950275
%e A076391(1990391) = 30712753
%e A076391(2528055) = 41463747
%e A076391(4853400) = 45117343
%e A076391(7427594) = 112401242
%e A076391(96166990) = 116579541
%t a = ContinuedFraction[ Chop[ N[ ArithmeticGeometricMean[1, I]/(1 + I), 10^4]]]; b = 0; Do[ If[ a[[n]] > b, Print[a[[n]]]; b = a[[n]]], {n, 1, 10^4}]
%Y Cf. A076390 & A076391.
%K nonn,more
%O 1,3
%A _Robert G. Wilson v_, Oct 09 2002
%E a(21)-a(26) from _Vaclav Kotesovec_, Oct 03 2019