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A344505
Decimal expansion of (exp(2*Pi) - 1) / (exp(2*Pi) + 1).
3
9, 9, 6, 2, 7, 2, 0, 7, 6, 2, 2, 0, 7, 4, 9, 9, 4, 4, 2, 6, 4, 6, 9, 0, 5, 8, 0, 0, 1, 2, 5, 3, 6, 7, 1, 1, 8, 9, 6, 8, 9, 9, 1, 9, 0, 8, 0, 4, 5, 8, 7, 6, 1, 4, 3, 6, 2, 6, 1, 2, 4, 1, 5, 9, 7, 8, 5, 4, 1, 2, 9, 8, 9, 8, 2, 8, 2, 1, 7, 1, 7, 6, 8, 5, 2, 8
OFFSET
0,1
FORMULA
Equals tanh(Pi).
Equals 1 / A175316.
Equals A175315 / A175314.
Equals 1 - 2/(1 + (Sum_{k>=0} 1/k!)^tau), where tau = 2*Pi = A019692.
EXAMPLE
Approximate 0.9962720762207499442646905800...
Approximate tau/(2 + tau^2/(6 + tau^2/(10 + tau^2/(14 + tau^2/(18 + tau^2/(22 + tau^2/(26 + tau^2/(30 + ...)))))))), where tau = 2*Pi.
MAPLE
Digits := 100: tau := 2*Pi: (exp(tau) - 1)/(exp(tau) + 1):
evalf(%)*10^86: ListTools:-Reverse(convert(floor(%), base, 10));
MATHEMATICA
RealDigits[Tanh[Pi], 10, 100][[1]] (* Amiram Eldar, May 22 2021 *)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Peter Luschny, May 22 2021
STATUS
approved