```Date: Jun 10, 2013 6:22 AM
Author: clicliclic@freenet.de
Subject: Re: The Charlwood Fifty

"Nasser M. Abbasi" schrieb:> > I've update the listing of the first 10 integrals. Added your optimal> results there, and also added result from Sage 5.4.> > http://www.12000.org/my_notes/ten_hard_integrals/index.htm> > Each integral is now on a separate web page instead of them> all on the same page to make it easier to see the results> of each.> > There is also a pdf file.> > Here is a quick summary of the first 10 integral results,> I just counted if CAS gave result or not. No checking for> anything else. Some results are clearly not optimal and> few results take many pages.> > 1. Mathematica: did 1,2,3,4,6,8,9,10  did not: 5,7> 2. Maple: did 1,2,3,4,5,6,7,8         did not: 9,10> 3. Rubi4: did 2,3(?),4,5,6,7,8,9,10   did not: 1> 4. Sage: did: 1,2,3,4,7,9             did not: 5,6,8,10> > I do not understand Rubi4 result for 3. I do not know what> Subst[....] is supposed to mean, but I have not looked it> up, I am sure it is explained somewhere. Any errors, please> let me know.> I noticed that your MMA and Rubi integrands for problem #7 have andextra outer root.I strongly suspect that "Sage" always means "Maxima" (not e.g. "Sympy"):see the Runtime Error Message for problem #8.Rubi's SUBST means "substitute": SUBST(a+b,b,c+d) = a+(c+d). SinceRubi's answer to problem #3 contains an unresolved integral inside theSUBST statemant, it must be counted as "not done".Martin.
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