A composition theorem for 𝛿-codes

Yang, C. H.

doi:10.1090/S0002-9939-1983-0712655-2

A composition theorem for $\delta$-codes
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Proc. Amer. Math. Soc. 89 (1983), 375-378 Request permission

Abstract:

If Golay complementary sequences (or equivalently a two-symbol $\delta$-code) of length $n$ and a Turyn $\delta$-code of length $t$ exist then four-symbol $\delta$-codes of length $(2n + 1)/t$ can be composed. Therefore new families of Hadamard matrices of orders $4uw$ and $20uw$ can be constructed, where $u = ({2^{\alpha + 1}}{10^b}{26^c} + 1)t$ for odd $t \leqslant 59$ or $t = {2^d}{10^e}{26^f} + 1$ (all $a$, $b$, $c$, $d$, $e$, and $f \geqslant 0$), and $w$ is the order of Williamson matrices.

References

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Computation of certain Hadamard matrices

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