New: combinatoricsAll contenthive-129948hive-196917krhive-150122zzanhive-180932hive-185836steemhive-188619hive-183959hive-166405hive-144064photographyhive-183397uncommonlabhive-101145hive-145157hive-184714hive-103599lifehive-165987hive-150943hive-139150hive-180106hive-109690TrendingNewHotLikersmarkgritter (59)in steemstem • 6 years agoPartitioning a set into listsThe Bell numbers count how many ways there are to partition N elements into sets. What if we want to partition the elements into ordered groups instead, as this Quora question asks? For…zipity (44)in mathematics • 6 years agothe Dehn–Sommerville equationsThanks to a video I saw on Youtube, I know now a way to prove both the relations I used in this post . First a few notations: Given a closed simply connected (without holes) domain on…markgritter (59)in steemstem • 6 years agoCounting the Number of 2-State 2-Dimensional Symmetric Cellular AutomataSuppose we have a two-state cellular automaton using the Moore neighborhood , which counts both orthogonal and diagonal neighbors. How many possible rules are there? With 9 cells total…markgritter (59)in python • 6 years agoPlotting all integer lattice paths from (0,0) to (3,5)If you start at (0,0) and can take one step at a time either north (0,+1) or east (+1,0), how many different ways are there to get to (3,5)? I wanted to augment this answer on Quora with a…markgritter (59)in mathematics • 6 years agoHow many 3-clubs can a graph have?A K-club on a graph is a subset of the vertices such that the diameter of the induced subgraph is less than or equal to K. "Induced subgraph" just means "pick all the edges which both endpoints in…markgritter (59)in stemq • 7 years agoHow many "incomplete open hypercubes" are there in four dimensions?Sol LeWitt's artwork "Incomplete Open Cubes" enumerates all distinct connected sets of edges of the cube which do not collapse into a smaller dimension (a figure that lies in the plane, or a single…markgritter (59)in programming • 7 years agoDiscard Trees: a data structure for finding nonintersecting combinationsA "discard tree" is a data structure I invented that is keyed by bitvectors representing K-combinations. It permits us to efficiently find all bitvectors that do not intersect with the search…markgritter (59)in mathematics • 7 years agoMinimal covering combination setsIn abstract terms: Given an N-element set, how many L-element subsets do we need so that every K-element subset is a superset of one of the L-element subsets? Let's express this by saying that the…drdawud (42)in mathematics • 7 years agoBasic Combinatorics, Part TwoImage source: In my previous post, I introduced some basic concepts in combinatorics. If you haven't read the previous post, you can do so here . Arranging objects when some objects are…boucaron (57)in science • 8 years agoFree Books: M. Lothaire's Books on Combinatorics on WordsTwo Books made freely available by "M.Lothaire" (M.Lothaire is a collective name chosen by the authors). It is all about "combinatorics on words" with theory, algorithms applied to…jackeown (48)in math • 8 years agoSimple Counting QuestionHow many ways are there to place 20 generic balls into 4 unique bins? This is a simple combinatorics question and I'll post a cool way of thinking about the answer tomorrow...leave any guesses in…mckeown12 (35)in introduceyourself • 8 years agoHello Steemit! I'm a math grad student in Miami, Florida.I heard about steemit from my awesome brother Jack, @jacKeown. He told me it would be a good community for me to become a part of so I plan to post a lot about the things I'm interested in; namely…seafood (51)in mathematics • 9 years agoA demo of an interactive Library of BabelI also wrote about similar topics in a companion postseafood (51)in mathematics • 9 years agoHave creatives "done everything before"? NO!: a combinatorial approachHere's a crazy idea you Steemers will probably really enjoy It's easy to feel overwhelmed by the collective creative output of humanity over the last two thousand years. So much has been said…
