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A060950
Rank of elliptic curve y^2 = x^3 + n.
14
0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 2, 0, 2, 1, 1, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 2, 1, 1, 1, 1, 0, 2, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 2, 1, 0, 0, 1, 1, 2, 0, 2, 1, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 0, 2, 1, 0, 1, 1, 0, 0, 0, 0, 0, 2, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1
OFFSET
1,15
COMMENTS
The curves for n and -27*n are isogenous (as Noam Elkies points out--see Womack), so they have the same rank. - Jonathan Sondow, Sep 10 2013
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000 (from Gebel)
J. Gebel, Integer points on Mordell curves [Cached copy, after the original web site tnt.math.se.tmu.ac.jp was shut down in 2017]
FORMULA
a(n) = A060951(27*n) and A060951(n) = a(27*n), so a(n) = a(729*n). - Jonathan Sondow, Sep 10 2013
EXAMPLE
a(1) = A060951(27) = a(729) = 0. - Jonathan Sondow, Sep 10 2013
PROG
(PARI) a(n) = ellanalyticrank(ellinit([0, 0, 0, 0, n]))[1] \\ Jianing Song, Aug 24 2022
(PARI) apply( {A060950(n)=ellrank(ellinit([0, n]))[1]}, [1..99]) \\ For PARI version < 2.14, use ellanalyticrank(...). - M. F. Hasler, Jul 01 2024
CROSSREFS
Cf. A081119 (number of integral solutions to Mordell's equation y^2 = x^3 + n).
Sequence in context: A182886 A108731 A235168 * A039976 A287267 A317540
KEYWORD
nonn,nice
AUTHOR
N. J. A. Sloane, May 10 2001
EXTENSIONS
Corrected by James R. Buddenhagen, Feb 18 2005
STATUS
approved