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A002946
Continued fraction for cube root of 3.
(Formerly M0408)
3
1, 2, 3, 1, 4, 1, 5, 1, 1, 6, 2, 5, 8, 3, 3, 4, 2, 6, 4, 4, 1, 3, 2, 3, 4, 1, 4, 9, 1, 8, 4, 3, 1, 3, 2, 6, 1, 6, 1, 3, 1, 1, 1, 1, 12, 3, 1, 3, 1, 1, 4, 1, 6, 1, 5, 1, 2, 1, 3, 3, 11, 8, 1, 139, 8, 2, 8, 5, 1, 2, 2, 2, 2, 3, 1, 1, 2, 1, 1, 1, 52, 2, 46, 2, 2, 3
OFFSET
0,2
REFERENCES
H. P. Robinson, Letter to N. J. A. Sloane, Nov 13 1973.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
S. Lang and H. Trotter, Continued fractions for some algebraic numbers, J. Reine Angew. Math. 255 (1972), 112-134.
S. Lang and H. Trotter, Continued fractions for some algebraic numbers, J. Reine Angew. Math. 255 (1972), 112-134. [Annotated scanned copy]
G. Xiao, Contfrac
EXAMPLE
3^(1/3) = 1.44224957030740838... = 1 + 1/(2 + 1/(3 + 1/(1 + 1/(4 + ...)))). - Harry J. Smith, May 08 2009
MAPLE
with(numtheory): cfrac(3^(1/3), 80, 'quotients'); # Muniru A Asiru, Nov 02 2018
MATHEMATICA
ContinuedFraction[Power[3, (3)^-1], 120] (* Harvey P. Dale, May 11 2011 *)
PROG
(PARI) { allocatemem(932245000); default(realprecision, 21000); x=contfrac(3^(1/3)); for (n=1, 20000, write("b002946.txt", n-1, " ", x[n])); } \\ Harry J. Smith, May 08 2009
(Magma) SetDefaultRealField(RealField(100)); ContinuedFraction(3^(1/3)); // G. C. Greubel, Nov 02 2018
CROSSREFS
Cf. A002581 (decimal expansion).
Cf. A002353, A002354 (convergents).
Sequence in context: A098554 A226081 A109201 * A286477 A277230 A218534
KEYWORD
nonn,cofr
EXTENSIONS
Offset changed by Andrew Howroyd, Jul 04 2024
STATUS
approved