A002358 Numerators of convergents to cube root of 5. (Formerly M1429 N0563)

1, 2, 5, 12, 53, 171, 566, 737, 4251, 4988, 9239, 41944, 428679, 7329487, 7758166, 115943811, 123701977, 239645788, 731522646953, 731762292741, 1463284939694, 2195047232435, 3658332172129, 5853379404564, 9511711576693, 24876802557950, 59265316692593

Offset

1,2

References

D. H. Lehmer, Guide to Tables in the Theory of Numbers. Bulletin No. 105, National Research Council, Washington, DC, 1941, p. 67.

P. Seeling, Verwandlung der irrationalen Groesse ... in einen Kettenbruch, Archiv. Math. Phys., 46 (1866), 80-120.

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

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Mathematica

Numerator[Convergents[5^(1/3), 30]] (* Vincenzo Librandi, Sep 08 2013 *)

Prog

(PARI) a(n)= contfracpnqn(contfrac(5^(1/3), n))[1, 1]; \\ Michel Marcus, Sep 07 2013

Crossrefs

Cf. A002357, A005481.

Sequence in context: A067578 A109139 A038576 * A083699 A064636 A355991

Adjacent sequences: A002355 A002356 A002357 * A002359 A002360 A002361

Keyword

nonn,frac

Author

N. J. A. Sloane, Herman P. Robinson

Extensions

More terms from Vincenzo Librandi, Sep 08 2013

Status

approved