Pretty much all books are scanned one way or another

Or are you using a metaphor? :O

@Sabಠ_ಠ t'es d'où toi ?

@Sabಠ_ಠ Someone did I guess, and AFAIK most universities give you digital access to those and journals in digital form

@GabrielR. Ile Maurice. :)

True too

Nous avons notre alliance française ici :)

ah c'est cool !

@MickLH Journals are one thing. But books are hard to scan.

Fun fact: The people who were scanning books to put on Google Books actually had some fun while doing it. :

J'ai passé du temps en France l'été passé ... J'espère vous recontrer tous la prochaine fois :P

@Sabಠ_ಠ Well it should have been produced digitally in the first place anyways

How did they have fun?

Chui pas francais @TedShifrin

Oui, je sais, @Sab ... @Sami non plus. Ça ne nous défend pas de se rencontrer :P

Theoretically we can just digitize everything once, and then work forward from there... digital from the get go. After that we should never have more than a napkin or whiteboard full to transcribe

@TedShifrin Check this: newyorker.com/online/blogs/books/2013/12/…

oh oui @Ted préviens nous si tu viens à Paris un de ces jours

J'ai des amis qui etudient la medecine en france.

t'es à Paris, @Gabriel? J'étais là bien sûr l'été dernier.

@Ted oui

@TedShifrin Do you allow (programmable) calculators?

@Gabriel Who did Israel vote for?

nope @685-252, not I.

Most courses don't allow calculators I gues.

We are not allowed even in Calculus

@TedShifrin not at all

no electronics

A lot of teachers allow basic calculators in class, but programmable, no, as students could type in the whole book if they wanted to.

We are strictly not allowed any here. I guess it's good in some ways though.

We have students all over the US now who cannot add $1/2+1/3$ without a calculator. They have no sense for anything. This is deplorable.

Sweden gave us 1 point !!! Unbelievable

@TedShifrin Don't they teach these in primary?

@TedShifrin true

@Studentmath I don't know

Yes, but we have hundreds of thousands of kids who don't learn.

I read an article where US is ranked very low in maths. But on the other side US has got the best universities.

Doesn't make sense, eh? @Sab

@TedShifrin I think I told you, but I saw the answer $18-\frac{28}{3} = 8.67$ the other day.

Totally makes sense @TedShifrin

Let me get out my calculator to check, @Mike.

That one is rather creative @Mike

@MikeMiller nice :-)

Wow, @Sab, I had never realized how tiny Mauritius is ! :)

My calculator gives me 8,2,3

I guess I know how to use it :3

@TedShifrin Is so small you can fit hundreds of it in a state of usa

I bet thousands :P

@TedShifrin Delaware!

@MikeMiller did you take off a point for rounding error?

New York is roughly 8 Mauritius. :P

Wait a minute, @Mike. So why is that student wrong? Do you require 4 decimals' accuracy?

smacks @DanielF :P

@TedShifrin I got $5/6$ but I checked it to be sure, is it because of all the fluoride they try to feed me here? :P

I guess he was wrong since the expected answer was exactly 8 and 2/3

WOW, really, @Sab? I guess I'm misled by the map.

@TedShifrin I didn't mark him wrong.

You were just astonished that someone resorted to a calculator. I'm no longer so astonished, although I don't teach too many courses where this is an issue.

@685-252 Nope.

I'm sure that would have demoralized him.

But there was an error

Well, I do computational homework on WeBWork, and I allow them to use calculators/Wolfram Alpha/Mathematica/ etc. for that. But they know that on tests they are on their own.

Ahh Webwork. I love this thing :D

So if they cannot row-reduce by hand or compute integrals by hand, they're in bigggg trouble.

In fact I got one due Monday

Eitherway, @MickLH if you could anyhow take a look and tell me what you think.. I can find a way to show such a flow is feasible on even n. But I know it is. It's some sort of a complex game of adding and substracting I can't follow. math.stackexchange.com/questions/788479/…

Formidable @Sab :)

I wrote about 300+ WeBWork problems for my multivariable math class ...

wow

I guess it's the same here

They write like 3 different variants for each webwork

No, most people use problems that other people have written :)

Ahh

I get your point. You actually WROTE them. That's on another level :D

WeBWork is written so that students all get randomized numbers in the problems ... In my case, often randomized functions (not just the parameters varying).

Here they use questions I can find with google

LOL @Sab. You prove all my points :)

Yep :P

Foutu, quoi ...

mdr

@Studentmath Lol I gave it a read, too formal sorry, don't hold your breath on my answer

Thanks anyhow :)

@Studentmath, you're just too recondite for us all.

I wish, it would at least mean I -know- something :P

I'm sure you know several somethings.

I'm only useful if you can fit the problem into about 8 seconds of attention span

Sigh @Mick

But you can use images, and you can preload me with anchored ideas first

not to mention caffeine

nonono lol that reduces me to 3 seconds

Oy.

I saw your name in Spivak @TedShifrin So amazing :D

Let me try to rephrase the question into a problem solving game @Mick

Yup, @Sab. Not the only book (besides my own) :P

What topics is your book on @TedShifrin?

abstract algebra, linear algebra, multivariable math (linear + multivariable + lots of proofs and analysis + manifolds), differential geometry (free .pdf)

:o

I guess you could give me some tips on proofs :D

C'est pas grand'chose :)

Oh que oui. *Accidentally used spoken french :P *

Is linear algebra free of right as well ? @Ted

What proofs are you working on?

We have n numbers $1,2,3,...n$. n is even. Each number may connect to another number - if it does, it gets a value. The value it gets is anything between 0 to (number one - number two), and the sign +/- is assigned - ah darn it, too complicated..

Nope, @Gabriel. Not as long as the publisher has a stake in it.

For now we did only induction and contradiction. But we did proofs for derivatives, rolle's theorem, mvt, some corollary of the mvt etc

@Studentmath ... I was following that far.

you might want to report this then gen.lib.rus.ec/book/… @Ted

Ah, are you actually taking a Spivak course, @Sab?

Oh. Let me try to go on then :P

@TedShifrin Nop Stewart course

@GabrielR. You can't get the Russians...

I'm not a fan of the book though.

@Studentmath Can you define "connect" and "+/- assigned" ? It's really not about the complexity for me, it's really just that I can set down my pen on the desk im sitting at, and 10 seconds later say "Where's my pen!"

I want to buy Spivak but I can't find it anywhere here.

I found one in the library but a postgrad student loaned it for 5 months

Too bad

:D I will try to make it as clear as possible.

Oh, right, you told me Stewart before. It gives me error messages, @Gabriel.

You could order Spivak directly from him, but I don't know what shipping would cost to your corner of the world. But the book is relatively cheap.

I went to a bookstore and they told me it would cost about $100

I know all sorts of people pirate books. I think there's nothing much we can do.

@Ted: What's your stand on piracy?

A physical book and an ebook are 2 different worlds.

ah, Spivak is no longer selling directly. He refers people to Amazon.

I'm not a fan, @Fernando, but it's the way of the future. I've fought with my publishers about costs and quality control, and I've lost. So I give up.

For someone who never read a book before joining uni, and for someone who uses his computer for hours everyday I find a physical book better than an ebook.

Well, I can confirm I'm now looking at your book @TedShifrin

Wow @Sab, je suis bien impressionné!

We have n numbers 1 to n, where n is even. Now, every number starts with an attached value, call it f(n), which is 0. We may add connections between numbers - say, connect 1 to 3, 4 to n, so on. When we connect two numbers, each has its value changed. The changed value goes like this: it is capped by |number one - number two|. The attached sign to the value is given like this: take number 2> number 1, then if |number 1 - number 2| is odd number 2 gets -, number 1 gets +. If it's even

How'd you do that, @Mike?

@TedShifrin The website lets you download it... the download button above

The other way around. We start when we connect every -odd- number to n. Now, without changing that, we want to get all the numbers besides 1 and n to have value 0. How do we connect them to get that.

@MikeMiller Did you just admitted piracy to the author? lol :D

Sure.

:P

@TedShifrin this link lib.freescienceengineering.org/view.php?id=869908 is up... It's not even a scan, it's the original pdf :(

I don't steal from Ted very often, so I'm sure he'll forgive me this once.

Mmm if $\int_a^b f(x)^2 \mathrm{d}x = A$, how can $\int_a^b f(x)\mathrm{d}x$ be expressed through $A$ ?

Also, n can't be connected to the evens (I don't want n to lose his value..)

I can't say I'm not a libgen fan

@N3buchadnezzar Not possible, IMO. Consider $a=1,b=2$, $f(x)=x^{-1}$.

@FernandoMartin Tenes whatsapp?

@Pedro: no, mi teléfono es de 1997

Sure you can, @FernandoMartin

How the f*** did they get a .pdf of it? I'm emailing the publisher on both of these. Thanks, @Gabriel. Crazy. I'm not getting much money from all that work, anyhow :)

@FernandoMartin But it has touchscreen.

It runs android 1.1

@TedShifrin I think your publishers are trying to handle the situation because some of the mirrors said "Link deleted by legal owner"

@TedShifrin Exactly my question. How can they get a pdf version when it's not for sale.

whatsapp needs >2.0 iirc

@FernandoMartin Vintage.

haha

There used to be a site called bookos, where you could literally download every math related book. I rinsed it off. But now its not there . A sad day it was.

@TedShifrin What's the geometric interpretation of higher order tangent vectors?

@PandaBear libgen is actually the mother project, and they don't give any f$$$ about legal action

Oh well, I guess I should just freely distribute everything to everyone :P

doitttt!

OK I think we can stop talking about how to pirate books now.

I don't know how to :P

Upload it to Piratebay @Ted

Never mind @Studentmath ... You can have my diff geo book for free :P

@TedShifrin Make a website, get a server and put all the books to download :D

They're like little pieces of osculating plane, and higher-order versions of that, @mike.

I like the smell of books. That's the only reason I'll buy a hard copy.

I like to pay for useful/enjoyful things :P

I like reading books in my hands.

That too ^

I like to flip pages.

Or we could flip you instead, @Sab :D

:D

I think it's called a library. We have a good one.

I will flip out @TedShifrin

@TedShifrin "and higher-order versions of that" feels like such a cop-out...

But yes, I see your point.

So much pun it makes me cry ;-;

Well, we look at osculating subspaces of various orders, @Mike. I wrote a paper about such things, actually ...

Do we?

You look at the span of derivatives up to order $k$ ...

@Sabಠ_ಠ sounds like pun

Officially, you can read about jet spaces in various books, @Mike.

This is punny @MickLH

I keep my students awake with sufficiently poor puns, @Sab.

I barely go to maths lectures these day, my teacher is too dull.

LOL ... I'll try not to put you to sleep.

OK, dinner time. Y'all misbehave without me.

I can't imagine a student sleeping in your class @TedShifrin :P

LOL, you have little basis to judge so far, @Sab.

Bon appetit! :D

Merci bien :)

guten apetit

Guess I gotta know jets too.

There's too much to know.

Oh darn, can start a bounty tomorrow only.. Bon appetit @Ted

@Studentmath I didn't see a solution in my minds eye, sorry bro, again don't hold your breath

Thanks again for looking :)

If I were stuck with solving that for some reason, I'd probably use a computer search to find example answers

And then bust out my handy dandy mind's eye telescope

And basically try to solve it through symbolic brute force, sorta trying things until I get a provable formula :P

and just hope, hope, hope that I get a better idea before I make it that far

It seems I am doomed into going over all the examples on n until n=12 or so.. which is really, really bad..

Thanks once again @Mick!

Lol no need for thanks I didn't help

You brought me back into doing all the examples :P

Although I had that "better" idea, which is to just fire the computer search off directly at the symbolic answer :P

Make an field of abstract syntax trees, then use a genetic algorithm to permute them until one solves lets say 100 trial cases

Writing a code for it is far too much for me :P

Then try to analyse the computer generated solution, and see if it's sane and provable

I barely know how to build an array in Java

But it could come really useful in here, I should really study it more

Well, I got the pattern. Now I just need to prove it.

Is anybody out there ?

nope

I'm