activity
20122022
most citedExistence results for pentagonal geometries

1 citations · 1 across the 7 of their papers we have counts for

collaborators

11 papers

math.CO2022

Group divisible designs with block size five: direct constructions

Anthony D. Forbes

We give direct constructions for 233 group divisible designs with block size five, mostly of type , .

math.CO2022

Group divisible designs with block size five

Anthony D. Forbes

We report some group divisible designs with block size five, including types and . As a consequence we are able to extend the known spectrum for 5-GDDs of type $g…

math.CO2021

Generalized pentagonal geometries

Anthony D. Forbes, Carrie G. Rutherford

A pentagonal geometry PENT(, ) is a partial linear space, where every line is incident with points, every point is incident with lines, and for each point , there…

math.CO2020

Pentagonal geometries with block sizes 3, 4 and 5

Anthony D. Forbes

A pentagonal geometry PENT(, ) is a partial linear space, where every line, or block, is incident with points, every point is incident with lines, and for each point…

math.CO2020★ 1 cited

Existence results for pentagonal geometries

Anthony D. Forbes, Terry S. Griggs, Klara Stokes

New results on pentagonal geometries PENT(k,r) with block sizes k = 3 or k = 4 are given. In particular we completely determine the existence spectra for PENT(3,r) systems with the…

math.CO2020

Designs for graphs with six vertices and ten edges -- II

Anthony D. Forbes, Terry S. Griggs

The design spectrum has been determined for ten of the 15 graphs with six vertices and ten edges. In this paper we solve the design spectrum problem for the remaining five graphs w…

math.CO2019

Group divisible designs with block size four and type

Anthony D. Forbes

We discuss group divisible designs with block size four and type , where , 6 and 7. For integers and , we prove the following. (i) A 4-GDD of type $…

math.CO2018

Group divisible designs with block size 4 and type g^u m^1 - II

Anthony D. Forbes

We show that the necessary conditions for the existence of 4-GDDs of type g^u m^1 are sufficient for g congruent to 0 (mod h), h = 39, 51, 57, 69, 87, 93, and for g = 13, 17, 19, 2…

math.CO2017

Theta Graph Designs

Anthony D. Forbes, Terry S. Griggs, Tamsin J. Forbes

We solve the design spectrum problem for all theta graphs with 10, 11, 12, 13, 14 and 15 edges

math.CO2016

Designs for 24-vertex snarks

Anthony D. Forbes

The design spectrum problem is solved for the thirty-eight 24-vertex non-trivial snarks.

math.CO2012

Snark Designs

Anthony D. Forbes

The main aim of this paper is to solve the design spectrum problem for Tietze's graph, the two 18-vertex Blanusa snarks, the six snarks on 20 vertices (including the flower snark J…