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unsystematic
Universe ⊆ Complexity
Complexity ⊆ Math
Math ⊆ Universe
an introduction to the mathematics of the infinite http://www.earlham.edu/~peters/writing/infinity.htm
nodes
- geometry/topology (Category Geometry)
- Topology Notes, etc+
general
- an atlas, with dots > http://www.math-atlas.org/
notes (to be absorbed...)
- hyperdimensional http://www.asahi-net.or.jp/~hq8y-ishm/hyper.html
- “A Visual Dictionary of Famous Plane Curves” http://xahlee.org/SpecialPlaneCurves_dir/specialPlaneCurves.html and other mathematical graphics http://xahlee.org/MathGraphicsGallery_dir/mathGraphicsGallery.html
- “geometry and the imagination” notes and lecture handouts http://www.geom.uiuc.edu/docs/doyle/mpls/handouts/handouts.html (or http://www.geom.uiuc.edu/docs/education/institute91/handouts/handouts.html)
- the ethnomathematics on line library http://www.ethnomath.org/
textbooks
- “A Computational Introduction to Number Theory and Algebra” > http://shoup.net/ntb/
- various online textbooks > http://www.math.gatech.edu/%7Ecain/textbooks/onlinebooks.html
Table Seatings
arranging a group into a number of tables so that everyone sits with everyone else.
A strict version is an affine plane. More generally we want a resolvable 2-design. Resovable is the parallelism. Maybe there is something like discrete hyperbolic geometry to deal with this, but we seem to have better combinatorial ideas below. https://en.wikipedia.org/wiki/Block_design#Resolvable_2-designs
Strict versions include Kirkman's Schoolgitl Problem, 15 children walk in groups of 3, can they do this so that all pairs of girls walk together exactly once over a whole week. https://en.wikipedia.org/wiki/Kirkman%27s_schoolgirl_problem https://oeis.org/search?q=schoolgirl&sort=&language=german&go=Suche
In other cases we need to either allow people not to meet, or to meet more often.
The Dagstuhl Happy Diner problem is the version where everyone meets at least once. https://github.com/fpvandoorn/Dagstuhl-tables https://oeis.org/A318240
Equitable Resolvable coverings seem also to be a more strict form, where we try to allow people to meet at most twice. https://www.researchgate.net/publication/227715273_Equitable_resolvable_coverings https://onlinelibrary.wiley.com/doi/epdf/10.1002/jcd.10024?saml_referrer
If we have people sitting at round tables and only interacting with their neighbours, then we have the Oberwolfach Problem: https://en.wikipedia.org/wiki/Oberwolfach_problem