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A359809
Decimal expansion of the positive solution to tanh(x) = x/2.
0
1, 9, 1, 5, 0, 0, 8, 0, 4, 8, 1, 5, 4, 5, 3, 7, 4, 8, 1, 3, 5, 3, 0, 0, 3, 0, 6, 1, 0, 0, 4, 8, 1, 5, 6, 5, 0, 5, 7, 3, 3, 6, 2, 5, 6, 8, 7, 8, 5, 9, 2, 8, 9, 8, 6, 1, 1, 3, 7, 4, 7, 3, 4, 6, 6, 4, 1, 3, 5, 6, 2, 3, 7, 6, 2, 6, 3, 1, 7, 3, 0, 9, 7, 7, 9, 3, 7, 6, 6, 1, 1, 3, 6, 8
OFFSET
1,2
COMMENTS
Also, point where e^-(x/2 - 1)^2 + e^-(x/2 + 1)^2 has its maximum.
EXAMPLE
1.91500804815453748135300306100481565...
MATHEMATICA
RealDigits[x /. FindRoot[Tanh[x] == x/2, {x, 2}, WorkingPrecision -> 110], 10, 105][[1]] (* Amiram Eldar, Jan 13 2023 *)
PROG
(PARI) localprec(199); digits(solve(x=1, 2, tanh(x)-x/2)\.1^150)
CROSSREFS
Cf. A309211.
Sequence in context: A178745 A114893 A089101 * A298512 A192930 A010168
KEYWORD
nonn,cons
AUTHOR
M. F. Hasler, Jan 13 2023
STATUS
approved