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Discussion
Over coffee, Bob said that he really liked this chapter. This material was full of cases of very concrete procedures for doing useful things. I like that.
Discussion
Over coffee, Bob said that he really liked this chapter. This material was full of cases of very concrete procedures for doing useful things. I like that. Yolanda offered a somewhat different perspective On the other hand, this last procedure only seems to work with interval orders and we still don't have a clue as to how to find the width of a poset in the general case. This might be very difficultlike the graph coloring problems discussed in the last chapter. Dave weighed in with Somehow I think there's going to be a fairly efficient process that works for all posets. We may not have all the tools yet, but let's wait a bit.
Not much was said for a while and after a pause, Carlos ventured that there were probably a lot of combinatorial problems for posets that had analogous versions for graphs and in those cases, the poset version would be a bit more complicated, sometime a little bit and sometimes a very big bit. Zori was quiet but she was thinking. These poset structures might even be useful, as she could imagine many settings in which a linear order was impossible or impractical. Maybe there were ways here to earn a few dollars.
Sasa Hakuna kifaa cha kupigia hesabu kinachoweza kufanya hesabu, lakini kifaa hicho kinaweza kutumiwa katika hesabu.
Ishara zinazotumiwa hapa
Vaa alama yoyote ya ufafanuzi kamili, picha, na maana ya kila herufi.
Maswali ambayo watu huuliza
Permutation or combination?
Ask whether order matters. A lock code is a permutation (order matters); a hand of cards is a combination (it does not).
What is a graph in this sense?
Dots (vertices) joined by lines (edges), not a plot. Road maps, social networks and molecules are graphs; questions like "is there a route" and "how few colours" are graph theory.
Sehemu za ukurasa huu zimebadilishwa kutoka kwa Keller & Trotter, Applied Combinatorics (CC BY-SA 4.0). Tumekamatwa na kukosolewa tena hapa; makosa ni yetu.
Mengi zaidi katika Combinatorics & Graph Theory
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