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1. • CommentRowNumber1.
   • CommentAuthorTobyBartels
   • CommentTimeJul 30th 2012
   • PermaLink
   Author: TobyBartels
   Format: MarkdownItexNew page: [[inclusion-exclusion principle]]

   New page: inclusion-exclusion principle

2. • CommentRowNumber2.
   • CommentAuthorZhen Lin
   • CommentTimeJul 30th 2012
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   Author: Zhen Lin
   Format: MarkdownItex> The principle of inclusion and exclusion is essentially a sheaf condition for measures; Genius! I'll have to remember this one.

   The principle of inclusion and exclusion is essentially a sheaf condition for measures;

   Genius! I’ll have to remember this one.

3. • CommentRowNumber3.
   • CommentAuthorTobyBartels
   • CommentTimeJul 30th 2012
   • PermaLink
   Author: TobyBartels
   Format: MarkdownItexI just thought of that, wondering what to put as the introduction.

   I just thought of that, wondering what to put as the introduction.

4. • CommentRowNumber4.
   • CommentAuthorTodd_Trimble
   • CommentTimeAug 2nd 2012
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   Author: Todd_Trimble
   Format: MarkdownItexThere's another POV on inclusion-exclusion: as a special case of Möbius inversion in lattices (the page on [[Moebius inversion]] could use some work). Comparison to the sheaf-theoretic insight should be worked out and recorded.

   There’s another POV on inclusion-exclusion: as a special case of Möbius inversion in lattices (the page on Moebius inversion could use some work). Comparison to the sheaf-theoretic insight should be worked out and recorded.

5. • CommentRowNumber5.
   • CommentAuthorMike Shulman
   • CommentTimeAug 6th 2012
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   Author: Mike Shulman
   Format: MarkdownItexYet another viewpoint on inclusion-exclusion is that it is a manifestation of the [additivity](http://www.math.ucsd.edu/~mshulman/papers/addtalk.pdf) of traces and Euler characteristics under colimits. Of course there is a connection to Mobius inversion through Leinster's work.

   Yet another viewpoint on inclusion-exclusion is that it is a manifestation of the additivity of traces and Euler characteristics under colimits. Of course there is a connection to Mobius inversion through Leinster’s work.