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

 

Logo

Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A013000 arctan(arctan(x)+tan(x))=2*x-16/3!*x^3+808/5!*x^5-99328/7!*x^7... 0
2, -16, 808, -99328, 22756480, -8373489408, 4518380796928, -3361577372366848, 3297920024665948160, -4125214890387616169984, 6407889739355365222383616, -12101572905129973895312965632 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..11.

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[ArcTan[ArcTan[x]+Tan[x]], {x, 0, nn}], x]Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, May 05 2012 *)

CROSSREFS

Sequence in context: A013137 A013990 A013005 * A013178 A084595 A273193

Adjacent sequences:  A012997 A012998 A012999 * A013001 A013002 A013003

KEYWORD

sign

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

EXTENSIONS

Corrected definition - N. J. A. Sloane, Dec 17 2011

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 November 19 03:53 EST 2017. Contains 294912 sequences.