ECM curve group order

Brain · 2010-12-08, 00:51

It may be a dumb question but I haven't found the answer yet:
Given: ECM factoring result: 2^exponent-1,B1, B2, Sigma, Factor found
Needed: Group order of the ecm curve (not the factor itsself)
What is the fastest way / best program to the the ecm group order?
All I have found is this.
A hint would be appreciated. Thanks.

fivemack · 2010-12-08, 01:00

http://www.mersenneforum.org/showthread.php?t=14184

put in your p and sigma then copy-and-paste the code in the box into the box on http://magma.maths.usyd.edu.au/calc/

2010-12-08, 00:51	#1
Brain Dec 2009 Peine, Germany 331 Posts	ECM curve group order It may be a dumb question but I haven't found the answer yet: Given: ECM factoring result: 2^exponent-1,B1, B2, Sigma, Factor found Needed: Group order of the ecm curve (not the factor itsself) What is the fastest way / best program to the the ecm group order? All I have found is this. A hint would be appreciated. Thanks.

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2010-12-08, 01:00	#2
fivemack (loop (#_fork)) Feb 2006 Cambridge, England 1100100110110₂ Posts	http://www.mersenneforum.org/showthread.php?t=14184 put in your p and sigma then copy-and-paste the code in the box into the box on http://magma.maths.usyd.edu.au/calc/