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A002666
Continued cotangent for square root of 2.
(Formerly M3983 N1652)
19
1, 5, 36, 3406, 14694817, 727050997716715, 2074744506784679417243551677046, 46045625970633183674340934067371917846908361831894602280765110
OFFSET
0,2
REFERENCES
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
D. H. Lehmer, A cotangent analogue of continued fractions, Duke Math. J., 4 (1935), 323-340. [Annotated scanned copy]
D. H. Lehmer, A cotangent analogue of continued fractions, Duke Math. J., 4 (1935), 323-340.
Eric Weisstein's World of Mathematics, Lehmer Cotangent Expansion.
PROG
(PARI) { default(realprecision, 10000); bn=vector(12); bn[1]=sqrt(2); for(n=2, 12, bn[n]=(bn[n-1]*floor(bn[n-1]) + 1)/(bn[n-1] - floor(bn[n-1]))); for (n=1, 12, write("b002666.txt", n-1, " ", floor(bn[n]))); } \\ Harry J. Smith, May 04 2009
CROSSREFS
Sequence in context: A118018 A318424 A156355 * A222592 A174507 A119483
KEYWORD
nonn
EXTENSIONS
More terms from Jeffrey Shallit
STATUS
approved