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A002667 Continued cotangent for Pi.
(Formerly M3171 N1286)
19
3, 73, 8599, 400091364, 371853741549033970, 253461181173408820488703379557217678 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

D. H. Lehmer, A cotangent analogue of continued fractions, Duke Math. J., 4 (1935), 323-340.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Harry J. Smith, Table of n, a(n) for n = 0..9

D. H. Lehmer, A cotangent analogue of continued fractions, Duke Math. J., 4 (1935), 323-340. [Annotated scanned copy]

Index entries for sequences related to the number Pi

PROG

(PARI) { default(realprecision, 10000); bn=vector(10); bn[1]=Pi; for(n=2, 10, bn[n]=(bn[n-1]*floor(bn[n-1]) + 1)/(bn[n-1] - floor(bn[n-1]))); for (n=1, 10, write("b002667.txt", n-1, " ", floor(bn[n]))); } \\ Harry J. Smith, May 04 2009

CROSSREFS

Sequence in context: A020517 A119017 A307232 * A145675 A336873 A121981

Adjacent sequences:  A002664 A002665 A002666 * A002668 A002669 A002670

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Jeffrey Shallit

STATUS

approved

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Last modified June 24 11:11 EDT 2021. Contains 345416 sequences. (Running on oeis4.)