In this note, we show that there is no \((945, 177, 33)\)-difference set in any group \(G\) of order \(945\) with a normal subgroup \(K\) such that \(G/K \cong \mathbb{C}_{27} \times \mathbb{C}_5\), and hence no cyclic difference set with such parameters exists. This fills one entry of Baumert and Gordon’s table with “No”.
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