login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A099282 Decimal expansion of the cosine integral at 1. 3
3, 3, 7, 4, 0, 3, 9, 2, 2, 9, 0, 0, 9, 6, 8, 1, 3, 4, 6, 6, 2, 6, 4, 6, 2, 0, 3, 8, 8, 9, 1, 5, 0, 7, 6, 9, 9, 9, 7, 5, 7, 8, 0, 3, 2, 5, 8, 5, 7, 3, 1, 8, 9, 4, 8, 0, 1, 3, 1, 8, 5, 4, 2, 4, 3, 6, 1, 3, 0, 3, 3, 0, 0, 2, 5, 0, 5, 6, 0, 5, 2, 8, 9, 6, 8, 4, 8, 1, 8, 3, 0, 9, 7, 3, 2, 2, 9, 9, 4, 6, 0, 4, 9, 4, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..104.

FORMULA

Equals -real(E_1(I)) = -(E_1(I)+E_1(-I))/2, where E_1(z)=integral[t >=1]{exp(-t*z)/t} is the exponential integral. - Stanislav Sykora, May 08 2015

EXAMPLE

I=0.337403922900968134662646203889150769997578032585731894801318542...

MATHEMATICA

RealDigits[ CosIntegral[1], 10, 105][[1]]

PROG

(PARI) a = real(-eint1(I)) \\ Stanislav Sykora, May 08 2015

(PARI) -intnum(x=1, [oo, I], cos(x)/x) \\ Charles R Greathouse IV, May 08 2015

CROSSREFS

Cf. A099281, A257535.

Sequence in context: A100587 A249383 A187419 * A002937 A085870 A096633

Adjacent sequences:  A099279 A099280 A099281 * A099283 A099284 A099285

KEYWORD

cons,nonn

AUTHOR

Robert G. Wilson v, Oct 08 2004

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified June 28 11:55 EDT 2017. Contains 288823 sequences.