Mathematics

Associated with Math.SE; for both general discussion & math qu...
Jul 3, 2023 08:07
ok never mind manually saved to pdf now, but weird I couldn't find that btn
Jul 3, 2023 07:23
i bookmarked chat conversation but can't find UI to find the bookmark
Jul 2, 2023 21:46
And weirdly this chat shows my rep from another stack exchange site, maybe it is a bug.. Anyway thanks and good night.
Jul 2, 2023 21:41
i mean see something in chat tomorrow
Jul 2, 2023 21:40
but I am not sure
Jul 2, 2023 21:40
@TedShifrin My main problem remains the N-1 term, somehow I couldn't follow your points where you explained it that is why I hope tomorrow I can see something there
Jul 2, 2023 21:39
@TedShifrin Hmm.. Ok I hope tomorrow when I come back to this chat it will be more clear for me. if you write an answer it will be even better potentially for others. Either way, thanks and good luck!
Jul 2, 2023 21:36
That's my problem currently :)
Jul 2, 2023 21:36
@TedShifrin " are in $N-1$." Why in N-1?
Jul 2, 2023 21:34
@TedShifrin Anyway if you don't feel like explaining anymore it is OK too, no big deal
Jul 2, 2023 21:34
@TedShifrin Ok I will try. But why is there dark in my room? First step 4 hours it is lit right? When the fourth hour ends I can already use new candle obtained from burning first two candles. Then I can use candle obtained by burning 3rd and 4th candles. And then I can create final new candle and immediately burn it
Jul 2, 2023 21:27
@TedShifrin Do you think you can do that?
Jul 2, 2023 21:27
@TedShifrin Sorry it is getting late here and I need to go to bed soon :( (due to work) It will be best I think if you write up an answer which conceptually explains and justifies use of N-1 and M-1
Jul 2, 2023 21:22
@TedShifrin in which my step is the error?
Jul 2, 2023 21:19
Let's go by example. N = 4 M =2
1) Burn 4 candles (4 hours)
2) Now we have 4 waxes
3) Make 2 New candles
4) Burn those two candles (2 more hours)
5) We have one more new candles due to step 4
6) Burn that one too (1 more hour)
7) We have that final unused and burnt candle
Jul 2, 2023 21:17
@TedShifrin When are N-1 already burned? after which step?
Jul 2, 2023 21:16
@TedShifrin why N-1 is used in nominator, that part I still can't follow :( sorry.
Jul 2, 2023 21:15
@TedShifrin Also one thing out of curiosity, in this response "Maybe you read it after the last candle had burned out, @george.
" it was humor when I said about illumination right ? :) Just asking out of curiosity if I "got" it no big deal
Jul 2, 2023 21:14
@TedShifrin Not sure what you mean
Jul 2, 2023 21:13
by N-1
Jul 2, 2023 21:13
@TedShifrin I thought by -1 he was referring that in the FINAL moment you have one unused burnt candle left
Jul 2, 2023 21:12
@TedShifrin Does N-1 make sense too?
Jul 2, 2023 21:11
@TedShifrin How did you see the formula from examples, didn't you just assume "k+[(k-1)/(m-1)]" in the induction and you assumed that because the books explanation said so, wasn't that the case?
Jul 2, 2023 21:09
That's not how you write explanations for people who you want to teach programming via puzzles
Jul 2, 2023 21:09
@TedShifrin Problem is cool but I was dissapointed by explanation
Jul 2, 2023 21:08
because of that :)
Jul 2, 2023 21:08
I threw out the book actuallyu
Jul 2, 2023 21:08
@TedShifrin I see at least I will not be suffering by thinking I was too dumb that I didn't realize how from this books explanation the solution followed
Jul 2, 2023 21:07
@TedShifrin "Well known argument" now you mean the books solution is clear to you?
Jul 2, 2023 21:06
@Jakobian yes that's a coincidence or how it is called :)
Jul 2, 2023 21:03
@TedShifrin i can find authors email in case you are interested
Jul 2, 2023 21:02
@TedShifrin no abou programming puzzles but due to the nature of solution i thought posting here
Jul 2, 2023 21:01
In my country
Jul 2, 2023 21:01
Author is coach of programming olympiad team
Jul 2, 2023 21:00
@TedShifrin sadly i dont think it is in english
Jul 2, 2023 20:46
@TedShifrin nah the first one didnt illuminate me either :)
Jul 2, 2023 20:43
@TedShifrin yeah i thought so my math got rusty, need to lookup complete induction. Anyway feel free to write up an answer too, maybe will be useful for someone else in future
Jul 2, 2023 20:38
@TedShifrin "Now check that with $f(k,m)=k+[(k-1)/(m-1)]$" -- where did this come from?
Jul 2, 2023 20:34
@TedShifrin that was my problem I wanted to justify usage of n-1 and m-1 ... i will look at your solution.
Jul 2, 2023 20:29
I mean initially i was surprised
Jul 2, 2023 20:28
@TedShifrin didn't try examples I was merely a bit angry that author just gave that brief explanation as solution. And i was surprised why i could not see how the solution directly flowed from his explanation
Jul 2, 2023 15:44
In above comment
Jul 2, 2023 15:44
There is problem in math education often things are not well explained to students, also in response to Jaakko above. I have similar problem above, there was solution in book which itself was unclear, see my link
Jul 2, 2023 13:12
I would appreciate some help on this Post:math.stackexchange.com/questions/4728916/…, so far haven't got satisfactory answer :(
 
Jul 2, 2023 16:39
I will look into this tomorrow thanks for trying
Jul 2, 2023 15:00
In other words i want a proof why your approach works instead of plugging in concrete numbers as you did :) how the author arrived at the solution of (n-1)/(m-1).
Jul 2, 2023 14:57
@MXXZ well yes and no, I can see how that works, but Why did you choose to group them in this manner :
i | ii | ii | ii | ii. And not some other combination. Say group them in three. Or initially separate two candles out instead of one. Thats the main question.
Jul 2, 2023 12:51
Let's follow like this. 1) You burn N candles and get N hours. 2) Now you have N burnt candles 3) Now you take out one burnt candle for some reason. 4) You have N-1 burnt candles now and you divide them on M-1 and get say H 5) Now you have H new candles and also one burnt candle from step 3. So what ? How do you proceed now?
Jul 2, 2023 12:51
"because of the divisbility condition, you can get that it is in fact an equality by following the argument above."- why divisibility implies equality? no this is not advanced book :(