On the density of the set of known Hadamard orders. (English) Zbl 1198.94090
Summary: Let \(S(x)\) be the number of \(n \leq x\) for which a Hadamard matrix of order \(n\) exists. Hadamard’s conjecture states that \(S(x)\) is about \(x/4\). From Paley’s constructions of Hadamard matrices, we have that \(S(x) = \Omega\left( \frac{x}{\log x} \right).\)
MSC:
| 94A60 | Cryptography |
References:
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