

A225053


Second terms of continued fractions for power towers e, e^e, e^e^e, ...


3




OFFSET

1,2


COMMENTS

It was conjectured (but remains unproved) that none of the power towers e, e^e, e^e^e, ... are integers. If so, the corresponding continued fractions contain at least 2 terms. If the conjecture fails, let the corresponding a(n) = 0.


LINKS

Table of n, a(n) for n=1..4.
Eric Weisstein's World of Mathematics, e.
Eric Weisstein's World of Mathematics, Power Tower
Wikipedia, Tetration, Open questions


EXAMPLE

a(3) = 9 because floor(1/frac(e^e^e)) = 9, since e^e^e ~ 3814279.10476.


MATHEMATICA

$MaxExtraPrecision = Infinity; terms = 4; Map[Function[x, ContinuedFraction[x, 2][[2]]], NestList[Exp, E, terms  1]]


CROSSREFS

Cf. A003417, A064107, A159825, A225064, A004002.
A056072 yields the first term of the continued fraction.
Sequence in context: A239068 A259833 A085138 * A215483 A153872 A242208
Adjacent sequences: A225050 A225051 A225052 * A225054 A225055 A225056


KEYWORD

nonn,hard,more


AUTHOR

Vladimir Reshetnikov, Apr 25 2013


STATUS

approved



