##### New appointments

Irene Pivotto joined the CMSC as a Research Associate on a Discovery Project entitled "Exact Structure in Graphs and Matroids"; she will be investigating minor-closed classes of binary matroids and graphs, in an attempt to provide exact structural theorems for some interesting and important classes.

##### SymOmega

SymOmega is a mathematical blog run by three CMSC Mathematicians, Michael Giudici, John Bamberg and Gordon Royle. Lately there has been some discussions about the future of mathematical journals and their mode of funding.

##### Arxiv

Find in one click all the publications of our members that are deposited on the Arxiv.

##### Conferences

### Third Workshop on Graphs and Matroids

Gordon and Irene went to Maastricht on 29 July - 4 August for the Third Workshop on Graphs and Matroids. An informal description of the workshop is on Symomega.

### Groups and Geometrics

Alice Devillers, Cheryl Praeger and Michael Giudici attended the Banff workshop on "Groups and Geometries'', Banff (Canada), 2-7/09/12.Alice Devillers gave a talk: "Automorphisms and opposition in twin buildings'' and Cheryl Praeger gave a talk called "Coprime subdegrees for primitive permutation groups and completely reducible linear groups''. Both talks can be viewed online.

### RICAM - Workshop

PhD student Sylvia Morris attended RICAM - Workshop on finite fields and their applications: character sums and their polynomials in Strobl, Austria, from the 2nd to 7th of September. She presented a talk entitled "Small order spreads of W(5,q)". *Website*.

### Combinatorics 2012

John Bamberg and Sylvia Morris attended Combinatorics 2012, Perugia (Italy), September 9 - 15, 2012. Sylvia presented a talk entitled "Small order spreads of W(5,q)" and John one entitled "Primitive generalised quadrangles".

### Conference on finite geometries in honour of Frank De Clerck

John Bamberg was an organiser, Cheryl Praeger an invited speaker (talk: Symmetry of Codes in graphs) and Sylvia Morris also attended this conference in Ferrara, Italy, September 17-18, 2012. *Website*.

### AustMS

Michael Giudici, Alice Niemeyer, Cai Heng Li and Cheryl Praeger attended the AustMS meeting, Ballarat, 24-27th Sept. They gave the following talks, all in the Group Actions special session:

Michael ''(k,L)-complexes and s-arc transitive graphs'',

Alice ''Complexity of collection in finite polycyclic groups'',

Cai Heng ''Edge-transitive maps'',

Cheryl ''Coprime subdegrees of primitive permutation groups''.

##### Recent visitors

Pablo Spiga, 06/08/2012 - 03/09/2012, Milano, Italy

Graham Farr 06/08/2012 - 10/08/2012, Monash.

Bill Smyth has made his first visit as adjunct professor. Bill is a Professor Emeritus from McMaster University Canada, experts in combinatorics on words and string algorithms, he has visited Western Australia annually for many years.

Costas Ilioupoulos has made his first visit as adjunct professor. He also is an expert in combinatorics on words and string algorithms.

##### News

John Bamberg has been awarded an ARC Future Fellowship commencing in 2012.

Sylvia Morris visited Nicola Durante (Universita degli Studi di Napoli Federico II) from the 20th of August to the 1st of September and worked with him in the area of maximal arcs.

Mark Ioppolo and David Raithel have started a PhD, both under the cosupervision of John Bamberg, Alice Devillers and Cheryl Praeger.

Cheryl Praeger was elected Vice President of the International Commission for Mathematical Instruction (ICMI) at the ICMI General Assembly in Seoul in July. The term of this office is 2013-2016.

Cheryl Praeger was reappointed as Associate Editor of Mathematics of Computation.

##### Papers

### Published papers

Carmen Amarra, Michael Giudici and Cheryl E. Praeger, Quotient-complete arc-transitive graphs. European J. Combin. 33 (2012) 1857-1881.

John Bamberg, Alice Devillers, and Jeroen Schillewaert, Weighted intriguing sets of finite generalised quadrangles. Journal of Algebraic Combinatorics, Volume 36(1) (2012) 149-173.

Andrew D. Cannon, John Bamberg and Cheryl E. Praeger. A classification of the strongly regular generalised Johnson graphs. Annals of Combin. 16, no. 3 (2012), 489-506.

Alice Devillers, Wei Jin, Cai Heng Li and Cheryl E. Praeger, Line graphs and 2-geodesic transitivity, Ars Math. Contemp. 6 (2013) 13-20.

Alice Devillers, Bernhard Muhlherr, Hendrik Van Maldeghem, Codistances of 3-spherical buildings, Mathematische Annalen Volume 354(1) (2012) 297-329 .

Alice Niemeyer, Tomasz Popiel and Cheryl E. Praeger, Algorithms to identify abundant p-singular elements in finite classical groups. Bull. Austral. Math. Soc. 86 (2012) 50-63.

Cheryl Praeger, Laszlo Pyber, Pablo Spiga and Endre Szabo. Graphs with automorphism groups admitting composition factors of bounded rank. Proc. Amer. Math. Soc. 140 (2012) 2307-2318.

Cheryl Praeger, Pablo Spiga and Gabriel Verret, Bounding the size of a vertex-stabiliser in a finite vertex-transitive graph. J. Combin. Theory, Series B. 102 (2012) 797-819

Cheryl Praeger and Csaba Schneider. Embedding permutation groups into wreath products in product action. J. Austral. Math. Soc. 92 (2012), 127-136

Cheryl Praeger and Akos Seress, Regular semisimple elements and involutions in finite general linear groups of odd characteristic. Proc. Amer. Math. Soc. 140 (2012) 3003-3015.

### Accepted Papers

Simon Ball, John Bamberg, Alice Devillers, Klara Stokes, An alternative way to generalise the pentagon, accepted in J. Combin. Designs.

John Bamberg, Anton Betten, Cheryl E. Praeger and Alfred Wassermann. Unitals in the Desarguesian projective plane of order sixteen, accepted in J. Stat. Planning Inf.

Scott Brown, M.Giudici, S.P. Glasby and Cheryl E. Praeger, Proportion of cyclic matrices in maximal reducible matrix algebras, accepted in J. Algebra.

T. Dobson, Cai Heng Li, Pablo Spiga, Transitive permutation groups with a regular abelian Hall subgroup, accepted in Comm. Algebra

Simon Guest and Cheryl E. Praeger. Proportions of elements with given 2-part order in finite classical groups of odd characteristic, accepted in Proc. Amer. Math. Soc. .

Cai Heng Li, Zai Ping Lu and Gaixia Wang, Vertex-transitive cubic graphs of square-free order, accepted in J. Graph Theory.

Cai Heng Li, Shujiao Song and Dianjun Wang, Finite locally-quasiprimitive graphs, accepted in Algebra Colloquium

Cai Heng Li, Shujiao Song and Dianjun Wang, A characteriaztion of metacirculants, accepted in J. Combin. Theory Ser. A.

### Submitted papers

L. Babai, S. Guest, Cheryl Praeger and R. A. Wilson, Proportions of r-regular elements in finite classical groups.

John Bamberg, On m-ovoids of dual twisted triality hexagons.

Alice Devillers, Wei Jin, Cai Heng Li and Cheryl E. Praeger, Finite 2-geodesic transitive graphs of prime valency.

Alice Devillers, Wei Jin, Cai Heng Li and Á. Seress, Local 2-geodesic transitivity of graphs.

Alice Devillers, James Parkinson, Hendrik Van Maldeghem, Automorphisms and opposition in twin buildings.

Silvio Dolfi, R. M. Guralnick, Cheryl E. Praeger and Pablo Spiga, Finite primitive permutation groups have at most two coprime subdegrees.

Neil Gillespie, Michael Giudici and Cheryl Praeger. Classification of a family of completely transitive codes.

Neil Gillespie, Daniel Hawtin and Cheryl Praeger. Elusive codes in Hamming graphs.

Neil Gillespie and Cheryl Praeger. Complete transitivity of the Nordstrom-Robinson codes.

Neil Gillespie and Cheryl Praeger. Diagonally neighbour transitive codes and frequency permutation arrays.

Michael Giudici and Aedan Pope, On bounding the diameter of the commuting graph of a group.

Cai Heng Li and Guang Rao, Self-complementary vertex-transitive graphs of order a product of two primes.