152 reputation
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bio website 4coloring.wordpress.com
location Rome
age 45
visits member for 3 years, 8 months
seen Dec 16 at 21:38

Aug
26
comment Kempe chain color swaps in a partially colored map
@Tyson. What I mean is: in partially Tait colored maps with faces of type F2, F3 or F4, if I have an impasse, Kempe chain color swapping may not work to solve an impasse, no matter how many swaps I try. Instead in maps without F2, F3 and F4, in all cases (not many: 40-50 cases) that I tryed, only by swapping colors I was able to solve the impasse. But this is just an hypothesis I'm verifying and is not related to the question. It is just the motivation of the question
Aug
26
comment Kempe chain color swaps in a partially colored map
@Tyson. Yes, by Fn (ex: F2, F3, F4) I mean faces bounded n edges. For the question, I don't want to count colorings in general (which I know it is hard), but starting from a specific configuration (the partially colored map in the picture) AND only proceding by Kempe chain color swaps (and non adding or removing colors from the map), how many different colorings can I have. I crossposted the question here because I had not received any answer (or hint) from math.stackexchange.com.
Aug
26
awarded  Curious
Aug
25
revised Kempe chain color swaps in a partially colored map
added 2485 characters in body
Aug
25
comment Kempe chain color swaps in a partially colored map
OK, thanks! I'll add some additional and more precise information later.
Aug
25
asked Kempe chain color swaps in a partially colored map
Aug
25
accepted Representations of regular maps (four color theorem)
Feb
8
comment Question about 3-regular graphs with a restriction (also fullerene and four color theorem)
Thanks again. Plantri is really a great program and it is so fast. Where my program takes 1 minute to elaborate all graphs of 15 faces, Plantri is istantaneous.
Jan
29
comment Question about 3-regular graphs with a restriction (also fullerene and four color theorem)
Thanks. So fast! I'm going to try this program right away.
Jan
29
accepted Question about 3-regular graphs with a restriction (also fullerene and four color theorem)
Jan
29
asked Question about 3-regular graphs with a restriction (also fullerene and four color theorem)
Mar
18
accepted Is there a formula to count how many different topological regular maps can be created with n faces (on a sphere)?
Jun
28
comment How many “different” colorings (excluding exchanges) exist for a given map (graph)?
Hi, how did you make these computations? I was planning to implement this feature into the program I'm building, but I'm having trouble to eliminate maps that "seems" different but that are actually the same map (Homeomorphic maps). See this other post: mathoverflow.net/questions/62328/…
Jun
8
revised Representations of regular maps (four color theorem)
edited tags
May
20
revised Representations of regular maps (four color theorem)
added 29 characters in body
May
19
revised Representations of regular maps (four color theorem)
added 225 characters in body
May
6
comment Representations of regular maps (four color theorem)
I really like this one based on the circle packing theorem, thanks!
May
4
awarded  Commentator
May
4
comment Representations of regular maps (four color theorem)
Hi Paul, I remember a comment made about this question by Noah Snyder. mathoverflow.net/questions/19240/…. "As far as I know there isn't anyone who is holed up in their attic thinking about only the 4-color theorem, instead there's a lot of people who every time they find a new tool think: hrm, I wonder if this tool would work on the 4-color theorem?" For example check the current reserch of Robin Thomas (people.math.gatech.edu/~thomas)
May
3
asked Representations of regular maps (four color theorem)