Week of
Week of
Written work: Your choices must be approved in advance by me. (This is to make sure they aren't too easy or too hard.)
Extra problems on duality: PostScript file.
Extra problems on projective geometry (Section 6.1). (The most important is the second one.)
Extra problems on the Möbius function.
Extra problems on hyperplane arrangements.
Problems on gain and biased graphs.
* means an advanced problem.
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Gain Graph GG1.
The gain group is Z4 . The gains on the diagram should be read in alphabetical order (from the "lower" to the "higher" letter). The funny-looking symbol that resembles "L" is 1. |