Re: nffactor() regression

[Igor Schein <igor@txc.com>]

On Mon, Jun 17, 2002 at 08:10:29PM +0200, Karim BELABAS wrote:
> On Thu, 13 Jun 2002, Igor Schein wrote:
> > the command below enters an infinite loop in 2.2.4 on Alpha Linux.  It worked
> > fine in 2.2.3
> >
> > nffactor(nfinit(polsubcyclo(19,6,y)),x^64-6384*x^62+18261761*x^60-31231019568*x^58+35925400902280*x^56-29635423138225800*x^54+18244443900381139917*x^52-8609789775431197305288*x^50+3173715440318358526295493*x^48-926253189958924421506713024*x^46+216130107574547887816493973792*x^44-40600173780591579547211667354912*x^42+6168621134132051706341715912515370*x^40-760139434277348135867991392951415744*x^38+76052955647065900426700689494084391434*x^36-6175311843554416772593815034596603661344*x^34+406137362468726923132369140307868626461744*x^32-21559959594011538596615817038079394912524336*x^30+919122010228667702998458013093798368177514170*x^28-31251399013676293208252728256910183010646331888*x^26+840017792466500823059432352741453680599704357258*x^24-17651171087877975905738341268934550365403253370816*x^22+285940694256111366646633973109729677687028435758880*x^20-3510138236669349338216717168753743720690200440965920*x^18+31970659328447652254136627725804141367170891626180389*x^16-210577501276259853380917767547980363666145460503950096*x^14+972633665701140285445722173171004563157651576027463941*x^12-3038789368329382179884462851269146550248145196800679728*x^10+6158927928896588396670590928896385649075890120481042824*x^8-7695135079270077790657693634058524039308535641860032904*x^6+5510293734552561962521574495431679567021222445632508873*x^4-1998778331104544904932086470347413669495129560426038280*x^2+273892744995340833777347939263771534786080723599733441);
> 
> I've fixed a few typos (and slightly improved diagnostics messages). The
> example above should be OK now.
> 
> nffactor should be much faster for simple examples also: the ones that can be
> dealt with without involving van Hoeij's algorithm.

Here's another infinite loop:

nffactor(nfinit(polcyclo(5,y)),x^48+12*x^46+948*x^44+7200*x^42+152361*x^40+815832*x^38+9475380*x^36+44654004*x^34+299137536*x^32+1335241260*x^30+5029216452*x^28+15282825984*x^26+37737671337*x^24+79579803672*x^22+143658877428*x^20+222699104460*x^18+303698198961*x^16+348787956312*x^14+312863646960*x^12+212893847424*x^10+111407984496*x^8+43762394880*x^6+11836253952*x^4+1904684544*x^2+136048896);

Thanks

Igor