Tags » Group Theory

Combinatorics of non-crossing partitions

The board is a result of of Bin Shu from East China Normal University visiting Iain Gordon at the University of Edinburgh. In Iain’s words: “We were discussing the combinatorics of non-crossing partitions, and its generalisations to a bunch of different finite groups. 61 more words


Legend of Prince Polyculture

There once was a boy named Prince Polyculture,

which he knew he was not,

and maybe even not-not,

which would be not a prince,

not. 463 more words


Parity in Molecular Orbital theory

Often seen with molecular orbitals (MOs) are the small letters u and g. U, ungerade, is the German for odd, and g, gerade, is the German for… 167 more words

Group Theory

Exploring groups of order 2^n p

Just some experiments I’m doing with the theorems I’m studying

Today I decided to explore (mainly as an exercise) finite groups of order , where and is an odd prime number. 224 more words


An elementary application of ping-pong lemma

Let us denote by the set of -matrices whose determinant is , and by the quotient . Our aim here is to prove that is a free product: 263 more words

Group Theory

Ranking and Unranking Permutations

A permutation on n elements is a rearrangement of the sequence . There are n! permutations on n elements. Given a permutation p on n… 731 more words