Skip to main content
13 events
when toggle format what by license comment
Jan 18, 2017 at 13:02 history edited Tony Huynh CC BY-SA 3.0
deleted 170 characters in body
Aug 10, 2010 at 12:17 comment added Fedor Petrov just a minor remark, the same without graphs: if two rows (say i-th and j-th) are equal to $r$, then each diagonal has at least two coincidences with $r$ (coincidence means coincidence of one of $n$ coordinate functionals). So, there are at least $n$ forbidden diagonals. If all rows are different, then all their complements are forbidden and we again have $n$ forbidden diagonals.
Aug 10, 2010 at 8:30 history edited Tony Huynh CC BY-SA 2.5
deleted 9 characters in body
Aug 10, 2010 at 7:37 comment added Tony Huynh Thanks Tsuyoshi! I edited the proof to handle that case separately.
Aug 10, 2010 at 7:35 history edited Tony Huynh CC BY-SA 2.5
added 206 characters in body
Aug 10, 2010 at 1:03 comment added Tsuyoshi Ito A clever argument! One minor comment: I do not think that the current proof of the lemma deals with the case where more than one vertex in [n]_c have exactly the same set of neighbors, but it can be fixed easily.
Aug 10, 2010 at 0:30 history edited Tony Huynh CC BY-SA 2.5
deleted 8 characters in body
Aug 10, 2010 at 0:24 history edited Tony Huynh CC BY-SA 2.5
added 972 characters in body
Aug 9, 2010 at 12:37 history edited Tony Huynh CC BY-SA 2.5
added 57 characters in body; added 7 characters in body
Aug 9, 2010 at 12:24 comment added Tony Huynh I suppose that I cannot generate diagonals that have exactly $n-1$ ones in this way, since if I fix $n-1$ rows, then I automatically fix the last one. But it seems that I can still get $2^n-n$ diagonals.
Aug 9, 2010 at 12:23 comment added Robin Chapman Not with $n=3$ you can't :-)
Aug 9, 2010 at 12:20 comment added damiano This seems to have a slight problem with the case of the configurations with exactly one zero.
Aug 9, 2010 at 12:18 history answered Tony Huynh CC BY-SA 2.5