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Denis Serre
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About the Hadamard conjecture

On the wikipedia article about Hadamard Matrix it says that "The smallest order that cannot be constructed by a combination of Sylvester's and Paley's methods is $92$"

But it also says that a new Hadamard matrix of size $nm$ can be created using Hadamard matrices of sizes $n$ and $m$.

Why isn't $23$ ($92=2 \times 2 \times 23$) the smallest size which cannot be created this way?