Saturday, May 1, 2021
Friday, April 30, 2021
Thursday, April 29, 2021
56 Three-Sets, 56 Spreads:
The Steiner Quadruple System S(3,4,8)
underlies the Steiner System S(5,8,24).
A previous update to the Oct. 29, 2019, post Triangles, Spreads, Mathieu:
Update of November 2, 2019 —
See also p. 284 of Geometry and Combinatorics:
Selected Works of J. J. Seidel (Academic Press, 1991).
That page is from a paper published in 1970.
That page, 284, contained an excerpt from
Bussemaker, F. C., & Seidel, J. J. (1970).
“Symmetric Hadamard matrices of order 36.”
(EUT report. WSK, Dept.of Mathematics and
Computing Science; Vol. 70-WSK-02).
Technische Hogeschool Eindhoven.
That paper is now available online:
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Tuesday, April 27, 2021
Thursday, April 22, 2021
A New Concrete Model for an Old Abstract Space
The April 20 summary I wrote for ScienceOpen.com suggests
a different presentation of an Encyclopedia of Mathematics
article from 2013 —
(Click to enlarge.)
Keywords: PG(3,2), Fano space, projective space, finite geometry, square model,
Cullinane diamond theorem, octad group, MOG.
Cite as
Cullinane, Steven H. (2021).
“The Square Model of Fano’s 1892 Finite 3-Space.”
Zenodo. https://doi.org/10.5281/zenodo.4718182 .
An earlier version of the square model of PG(3,2) —
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