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Discrete Hartley Transform

The discrete Hartley transform, DHT, is given by the matrix

The following structured, sparse matrix factorization represents a fast algorithm for a DHT, size 8, and has been automatically generated (even in the presented Latex format) using the package AREP.
fast algorithm DHT
Note that this algorithm requires 2 multiplications and 22 additions and is thus among the best ones known.

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