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Timeline for The motorcyclist's challenge

Current License: CC BY-SA 3.0

15 events
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Mar 10, 2017 at 9:42 history edited CommunityBot
replaced http://i1191.photobucket.com/ with https://i1191.photobucket.com/
Mar 14, 2012 at 12:45 comment added Eric @Brendan: Yes. But could that ever happen?
Sep 8, 2011 at 15:10 comment added Brendan McKay Is the motorcyclist allowed to drop a walker to the left of $X$?
Aug 11, 2011 at 4:14 history edited Eric CC BY-SA 3.0
added 418 characters in body
Aug 10, 2011 at 5:04 answer added Eric timeline score: 2
Aug 10, 2011 at 4:11 comment added Barry Cipra @fedja, in order for the feasible set for $n=2$ to be the entire first quadrant, the motorcyclist must be able to drive the faster walker backward (if that walker's pace is greater than or equal to 1).
Aug 10, 2011 at 3:47 answer added Barry Cipra timeline score: 1
Aug 10, 2011 at 3:22 comment added fedja A stupid but relevant question: can the motorcyclist drive the walkers backward? I guess not, but it would be nice to have it stated explicitly :).
Aug 10, 2011 at 2:30 comment added Eric @Gehard: Yes, reversals and transitions are instantaneous, and we assume multiple lanes only to avoid the walkers and motorcycle crashing into each other. But it seems that feasible sets are independent of choice of distance. Specifically, for ${a}_{1}=0$, ${a}_{3}=1$ to be feasible, all you need there is $0<{a}_{2}\leq 1/2$.
Aug 9, 2011 at 16:49 comment added Gerhard Paseman For n=3, there are some feasible sets with the fastest walker having velocity equal to 1 (and with enough distance, the slowest walker not walking at all) . I'm assuming multiple lanes and instantaneous reversals and transitions. Also, it might be useful to consider the feasibility of just doing the swapping of the kth fastest and kth slowest walkers for enough k. Gerhard "Ask Me About System Design" Paseman, 2011.08.09
Aug 9, 2011 at 12:44 comment added Eric @Fedor: The illustration can be seen now.
Aug 9, 2011 at 12:43 history edited Eric CC BY-SA 3.0
illustration display error fixed
Aug 9, 2011 at 10:11 comment added Fedor Petrov I do not see the illustration, only some Chinese characters and reference to baidu.
Aug 9, 2011 at 7:42 history edited Eric CC BY-SA 3.0
illustration added
Aug 9, 2011 at 7:25 history asked Eric CC BY-SA 3.0