John Cremona on Fri, 11 Jan 2002 08:33:02 +0000


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Re: Mordell Weil generator for y^2=x^3+7823


(In response to Igor's posting)

There are two normalizations of heights in use.  The one which gives
77.6 is one;  Pari uses the other for heights, though makes the
adjustment for the height pairing (so as to give appropriate values for
Birch-Swinnerton-Dyer applications).

Put another way, although Pari's height for this point is 77.6/2=38.8,
its value for the height pairing is 77.6.

John
-- 
 Prof. J. E. Cremona             |
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