Mathematics

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Sep 20, 2013 17:25
@robjohn: Just popping in to say that I noticed your answers to my old question. I don't have time to look closely at them now, but I will later (hopefully this afternoon). Thanks for posting them.
Jan 16, 2013 18:51
@OldJohn Either that, or we're both seeing things. :)
Jan 16, 2013 18:50
@JayeshBadwaik Following Old John's comment, I logged out, and there it was. I logged back in, and it was gone.
Jan 16, 2013 18:44
@JayeshBadwaik I see it on several other SE sites, too (also in Chrome) - just not on math.SE. Weird.
Jan 16, 2013 18:43
@JayeshBadwaik I see it on Stack Overflow, even in Chrome.
Jan 16, 2013 18:40
@JayeshBadwaik O.K., I see "About" when I use Firefox. But not with Chrome or Internet Explorer.
Jan 16, 2013 18:38
@JayeshBadwaik Interesting. Mine just has "Review Chat Meta Faq" across the top. No "About."
Jan 16, 2013 18:33
@JayeshBadwaik Where, exactly? I'm not seeing it.
Jan 16, 2013 18:29
@JasonBourne Thanks. I did find it, and I think it's a really good page, but if new users are going to get anything out of it then it needs to be obvious on the main site.
Jan 16, 2013 18:25
@robjohn: I noticed that there's now an "Informed" badge that you get for reading the entire "About" page. However, I can't find the link to the "About" page on the main site. It seems like that should be prominently displayed. Do you know anything about that?
Jan 16, 2013 18:25
@Tim: Thanks for the affirmation. :)
Jan 16, 2013 18:23
@OldJohn And I'm glad to hear I'm not the only one. :)
Jan 16, 2013 18:22
@OldJohn Re: Erdos and "simple arguments". I once needed the details of a two-line argument in a paper of Erdos. It took me two pages to fill everything in.
 
Jan 14, 2013 22:19
Sounds good. Best wishes! :)
Jan 14, 2013 22:18
You're probably right.
Jan 14, 2013 22:17
Yes. :)
Jan 14, 2013 22:16
I'd have to work through the details to make sure, but I'm pretty sure that it is.
Jan 14, 2013 22:16
It doesn't look like he uses those integral representations, though.
Jan 14, 2013 22:15
Well, this would only be the umpteenth time I've worked on something only to discover someone else has already done it. :)
Jan 14, 2013 22:14
I think you're right. :(
Jan 14, 2013 22:13
You're right. I guess ours is different.
Jan 14, 2013 22:11
The transformation $y_j = e^{u_j}$ gives the integral representation in eq. (3). That removes the log but introduces exp.
Jan 14, 2013 22:09
That's the transformation I was thinking of, too. I don't see yet how it removes the log. Maybe it isn't really the same as ours.
Jan 14, 2013 22:03
I'll have to take a closer look. I guess it needs a variable transformation to remove the log?
Jan 14, 2013 22:01
@Marvis Which formula?
Jan 14, 2013 21:57
Not sure. There are the Crandall, Borwein, and Zagier references, too.
Jan 14, 2013 21:53
Yes, it does.
Jan 14, 2013 21:48
Same here. I imagine we just need to work with them more.
Jan 14, 2013 21:47
For your work being new, I mean.
Jan 14, 2013 21:47
That's encouraging. :)
Jan 14, 2013 21:46
And the integrals I'm seeing involve logs. So they're more like the integral $\int_0^1 \log (1 + x) \log x \log (1- x) dx$ that Chris's sister asked about initially.
Jan 14, 2013 21:42
I'm not seeing the term "Euler sum" in his paper yet.
Jan 14, 2013 21:42
Or we could search for other articles that build more directly off of his so that we could find out exactly what is known about integral representations for Euler sums.
Jan 14, 2013 21:41
Or maybe your work could extend what he does.
Jan 14, 2013 21:41
And maybe your work is just repeating his.
Jan 14, 2013 21:41
@Marvis I just meant that if de Doelder has the same derivations you do then that's our first solid reference for your derivations.
Jan 14, 2013 21:35
Yes, thanks!
Jan 14, 2013 21:34
Does de Doelder have your integral representations?
Jan 14, 2013 21:34
No, I don't have access to it. (I miss Princeton's journal collection sometimes! I'm sure Stanford's is really good.)
Jan 14, 2013 21:33
Let me check.
Jan 14, 2013 21:31
@Marvis I would think so.
Jan 14, 2013 21:31
Here's a statement from that Flajolet and Salvy article: "Identities of low weight can sometimes be proved by special integral representations and functional properties of polylogarithms (de Doelder 1991)." So I guess we need to look up that de Doelder reference.
Jan 14, 2013 21:29
This article also has some: algo.inria.fr/flajolet/Publications/FlSa98.pdf. I verified one of the alternating Euler sums in my question with it.
Jan 14, 2013 21:27
Some of those conjectures may have been proven by now, as that article is almost 20 years old.
Jan 14, 2013 21:27
I don't know much about polylogs. I guess we would have to find out whether anyone else has used them to evaluate Euler sums.
Jan 14, 2013 21:26
There's a bunch of conjectures on page 26.
Jan 14, 2013 21:25
I think this article is the one that I found that had the most explicit evaluations: davidhbailey.com/dhbpapers/eulsum-em.pdf. See page 19.
Jan 14, 2013 21:22
Were you ever able to find out how to evaluate those other integrals in your answer (the ones that probably involved polylogs)?
Jan 14, 2013 21:21
Don't apologize! I think this one is the most promising, actually. :)
Jan 14, 2013 21:20
By the way, I think this is the third time you and I have discussed the possibility of writing a paper based on something from math.SE. :)