

A028939


Denominator of y coordinate of (2n)*P where P is generator for rational points on curve y^2+y = x^3x.


2



1, 1, 1, 125, 64, 24389, 2146689, 274625, 50202571769, 4302115807744, 1469451780501769, 13528653463047586625, 343216282443844010111, 63061816101171948456692661, 495133617181351428873673516736
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,4


REFERENCES

B. Mazur, Arithmetic on curves, Bull. Amer Math. Soc. 14 (1986), 207259; see p 225.


LINKS

Table of n, a(n) for n=1..15.


FORMULA

P=(0, 0), 2P=(1, 0), if kP=(a, b) then (k+1)P=(a'=(b^2a^3)/a^2, b'=1b*a'/a).


EXAMPLE

8P = (21/25, 69/125).


CROSSREFS

Sequence in context: A077495 A030668 A030678 * A195420 A080538 A104233
Adjacent sequences: A028936 A028937 A028938 * A028940 A028941 A028942


KEYWORD

nonn


AUTHOR

N. J. A. Sloane.


STATUS

approved



