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arXiv · 2509.10673

There exist Steiner systems $S(2,8,225)$ and $S(2,9,289)$

Ivan Hetman
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Abstract

In this note six Steiner systems $S(2,8,225)$ and four Steiner systems $S(2,9,289)$ are presented. This resolves two of $129$ undecided cases for block designs with block length $8$ and $9$, mentioned in Handbook of Combinatorial Designs.

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Ivan Hetman. 2026-03-26. There exist Steiner systems $S(2,8,225)$ and $S(2,9,289)$. https://doi.org/10.1002/jcd.70011

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