Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A081786
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A081786 Continued cotangent for log(3). +0
1
1, 21, 1591, 5623795, 60586207387643, 11771746654268128293298294264, 223879928814222731378358322195036233470100990978181612407, 60370531495558553873551440308434816125184142701829318337696802178075590153432959\ 525193229753905998692773283506988 (list; graph; listen)
OFFSET

0,2

FORMULA

log(3)=cot(sum(n>=0, n, (-1)^n*acot(a(n))); let b(0)=log(3), b(n)=(b(n-1)*floor(b(n-1))+1)/(b(n-1)-floor(b(n-1)) then a(n)=floor(b(n))

PROGRAM

(PARI) ?bn=vector(100); b(n)=if(n<0, 0, bn[n]); bn[1]=log(3); ?for(n=2, 10, bn[n]=(b(n-1)*floor(b(n-1))+1)/(b(n-1)-floor(b(n-1)))) ?a(n)=floor(b(n+1))

CROSSREFS

Cf. A002666, A002667.

Sequence in context: A118446 A130332 A035319 this_sequence A130039 A163928 A153848

Adjacent sequences: A081783 A081784 A081785 this_sequence A081787 A081788 A081789

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 10 2003

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 25 08:46 EST 2009. Contains 167481 sequences.


AT&T Labs Research