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A073745
Decimal expansion of csch(1).
7
8, 5, 0, 9, 1, 8, 1, 2, 8, 2, 3, 9, 3, 2, 1, 5, 4, 5, 1, 3, 3, 8, 4, 2, 7, 6, 3, 2, 8, 7, 1, 7, 5, 2, 8, 4, 1, 8, 1, 7, 2, 4, 6, 6, 0, 9, 1, 0, 3, 3, 9, 6, 1, 6, 9, 9, 0, 4, 2, 1, 1, 5, 1, 7, 2, 9, 0, 0, 3, 3, 6, 4, 3, 2, 1, 4, 6, 5, 1, 0, 3, 8, 9, 9, 7, 3, 0, 1, 7, 7, 3, 2, 8, 8, 9, 3, 8, 1, 2, 3, 6, 2, 4, 4
OFFSET
0,1
COMMENTS
csch(x) = 2/(e^x - e^(-x)).
By the Lindemann-Weierstrass theorem, this constant is transcendental. - Charles R Greathouse IV, May 14 2019
REFERENCES
Samuel M. Selby (ed.), CRC Basic Mathematical Tables, CRC Press, 1970, p. 218.
LINKS
Eric Weisstein's World of Mathematics, Hyperbolic Cosecant.
Eric Weisstein's World of Mathematics, Hyperbolic Functions.
FORMULA
Equals Sum_{k>=0} B(2*k) * (2 - 2^(2*k)) / (2*k)!, where B(k) is the k-th Bernoulli number. - Amiram Eldar, May 15 2021
EXAMPLE
0.85091812823932154513384276328...
MATHEMATICA
RealDigits[Csch[1], 10, 100][[1]] (* Amiram Eldar, May 15 2021 *)
PROG
(PARI) 1/sinh(1)
CROSSREFS
Cf. A068139 (continued fraction), A073742 (sinh(1)=1/A073745), A073743 (cosh(1)), A073744 (tanh(1)), A073746 (sech(1)), A073747 (coth(1)).
Sequence in context: A197841 A143347 A073448 * A086730 A249449 A357466
KEYWORD
cons,nonn
AUTHOR
Rick L. Shepherd, Aug 07 2002
STATUS
approved