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%I #15 Sep 15 2024 01:44:46
%S 2,5,21,219,12686,15636041,4101615513409,12983864742986180266005,
%T 588668718546098799238432431873920456606,
%U 93859726557327916653208320240553220872245170780539985934198524439788
%N a(n) = floor(e^e^(n/e^gamma)).
%C Assuming the Riemann hypothesis we have a(n) < A134716(n) for n >= 4.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/RobinsTheorem.html">Robin's Theorem</a>
%e a(3) = 219 because exp(exp(n/exp(gamma))) = 219.0062568829....
%t Table[Floor[E^E^(n/E^EulerGamma)], {n, 0, 9}]
%o (Magma) [Floor(Exp(Exp(n/Exp(EulerGamma(RealField(100)))))) : n in [0..9]];
%Y Cf. A001620, A134716, A058210.
%K nonn
%O 0,1
%A _Arkadiusz Wesolowski_, Sep 15 2012