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A073743
Decimal expansion of cosh(1).
39
1, 5, 4, 3, 0, 8, 0, 6, 3, 4, 8, 1, 5, 2, 4, 3, 7, 7, 8, 4, 7, 7, 9, 0, 5, 6, 2, 0, 7, 5, 7, 0, 6, 1, 6, 8, 2, 6, 0, 1, 5, 2, 9, 1, 1, 2, 3, 6, 5, 8, 6, 3, 7, 0, 4, 7, 3, 7, 4, 0, 2, 2, 1, 4, 7, 1, 0, 7, 6, 9, 0, 6, 3, 0, 4, 9, 2, 2, 3, 6, 9, 8, 9, 6, 4, 2, 6, 4, 7, 2, 6, 4, 3, 5, 5, 4, 3, 0, 3, 5, 5, 8, 7, 0, 4
OFFSET
1,2
COMMENTS
Also decimal expansion of cos(i). - N. J. A. Sloane, Feb 12 2010
cosh(x) = (e^x + e^(-x))/2.
Equals Sum_{n>=0} 1/A010050(n). See Gradsteyn-Ryzhik (0.245.5). - R. J. Mathar, Oct 27 2012
By the Lindemann-Weierstrass theorem, this constant is transcendental. - Charles R Greathouse IV, May 14 2019
REFERENCES
S. Selby, editor, CRC Basic Mathematical Tables, CRC Press, 1970, p. 218.
LINKS
Eric Weisstein's World of Mathematics, Hyperbolic Cosine
Eric Weisstein's World of Mathematics, Hyperbolic Functions
Eric Weisstein's World of Mathematics, Factorial Sums
FORMULA
Continued fraction representation: cosh(1) = 1 + 1/(2 - 2/(13 - 12/(31 - ... - (2*n - 4)*(2*n - 5)/((4*n^2 - 10*n + 7) - ... )))). See A051396 for proof. Cf. A049470 (cos(1)) and A073742 (sinh(1)). - Peter Bala, Sep 05 2016
Equals Product_{k>=0} 1 + 4/((2*k+1)*Pi)^2. - Amiram Eldar, Jul 16 2020
EXAMPLE
1.54308063481524377847790562075...
MAPLE
Digits:=100: evalf(cosh(1)); # Wesley Ivan Hurt, Nov 18 2014
MATHEMATICA
RealDigits[Cosh[1], 10, 120][[1]] (* Harvey P. Dale, Aug 03 2014 *)
PROG
(PARI) cosh(1)
CROSSREFS
Cf. A068118 (continued fraction), A073746 (sech(1)=1/A073743), A073742 (sinh(1)), A073744 (tanh(1)), A073745 (csch(1)), A073747 (coth(1)), A049470 (cos(1)).
Sequence in context: A019712 A020799 A199432 * A021652 A360778 A370427
KEYWORD
cons,nonn
AUTHOR
Rick L. Shepherd, Aug 07 2002
STATUS
approved