Problem with Prime95 ECM for M(665280) - Page 2

philmoore · 2003-09-24, 20:37

Just thought I'd second the request of wblipp on this. The easy error message to interpret is the "factor does not divide 2^p-1" error that comes up during initialization of ECM or P-1. What would be nice would be to find out what the offending factor is, since some of these highly composite exponents may have a factor list of over 100 factors. But the other error, due to a factor occurring twice, can lead to some rather bizarre and unexpected errors, including, "factor does not divide N!" messages, but also, simply missing a factor which should be found or reports of factors which are already in the factor list. Perhaps this kind of error could be caught with an independent script which checks the factor list for multiple factors rather than building something in to Prime95. An example of a duplicate factor which can be harder to catch would be if both 11 and 22033 = 11 * 2003 occur in the factor list, but 121 = 11^2 is not a factor. Any ideas on the easiest way to catch this sort of error?

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2003-09-24, 20:37	#12
philmoore "Phil" Sep 2002 Tracktown, U.S.A. 3·373 Posts	Just thought I'd second the request of wblipp on this. The easy error message to interpret is the "factor does not divide 2^p-1" error that comes up during initialization of ECM or P-1. What would be nice would be to find out what the offending factor is, since some of these highly composite exponents may have a factor list of over 100 factors. But the other error, due to a factor occurring twice, can lead to some rather bizarre and unexpected errors, including, "factor does not divide N!" messages, but also, simply missing a factor which should be found or reports of factors which are already in the factor list. Perhaps this kind of error could be caught with an independent script which checks the factor list for multiple factors rather than building something in to Prime95. An example of a duplicate factor which can be harder to catch would be if both 11 and 22033 = 11 * 2003 occur in the factor list, but 121 = 11^2 is not a factor. Any ideas on the easiest way to catch this sort of error?