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A307178 Decimal expansion of coth(1/2). 0
2, 1, 6, 3, 9, 5, 3, 4, 1, 3, 7, 3, 8, 6, 5, 2, 8, 4, 8, 7, 7, 0, 0, 0, 4, 0, 1, 0, 2, 1, 8, 0, 2, 3, 1, 1, 7, 0, 9, 3, 7, 3, 8, 6, 0, 2, 1, 5, 0, 7, 9, 2, 2, 7, 2, 5, 3, 3, 5, 7, 4, 1, 1, 9, 2, 9, 6, 0, 8, 7, 6, 3, 4, 7, 8, 3, 3, 3, 9, 4, 8, 6, 5, 7, 4, 4, 0, 9, 4, 1, 8, 8, 0, 9, 7, 5, 0, 1, 1, 5, 3, 0, 9, 2, 4, 0, 4, 7, 7, 1, 6, 1, 4, 0, 8, 0, 9, 1, 7, 0 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

By the Lindemann-Weierstrass theorem, this constant is transcendental. - Charles R Greathouse IV, May 14 2019

LINKS

Table of n, a(n) for n=1..120.

Index entries for transcendental numbers

FORMULA

Equals (exp(1)+1)/(exp(1)-1).

Equals (BesselI(3/2,1/2)/BesselI(1/2,1/2))+2.

Equals BesselI(-1/2,1/2)/BesselI(1/2,1/2).

EXAMPLE

2.163953413738... = 2 + 1/(6 + 1/(10 + 1/(14 + 1/(18 + ...)))).

MATHEMATICA

RealDigits[Coth[1/2], 10, 120][[1]] (* or *) BesselI[-1/2, 1/2]/BesselI[1/2, 1/2]

PROG

(PARI) cotanh(1/2) \\ Michel Marcus, Mar 28 2019

CROSSREFS

Cf. A016825 (continued fraction), A073747 (coth(1)).

Sequence in context: A284475 A285355 A316605 * A026191 A050137 A086111

Adjacent sequences:  A307175 A307176 A307177 * A307179 A307180 A307181

KEYWORD

cons,nonn

AUTHOR

Terry D. Grant, Mar 27 2019

STATUS

approved

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Last modified November 15 21:37 EST 2019. Contains 329168 sequences. (Running on oeis4.)