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Date: Wed, 20 Nov 2013 13:28:28 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: James Plank <plank@cs.utk.edu>
CC: Andrea Mazzoleni <amadvance@gmail.com>, Ric Wheeler <rwheeler@redhat.com>,
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        Btrfs BTRFS <linux-btrfs@vger.kernel.org>,
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Subject: Re: Triple parity and beyond
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On 11/20/2013 12:30 PM, James Plank wrote:
> Peter, I think I understand it differently.  Concrete example in GF(256) for k=6, m=4:
> 
> First, create a 3 by 6 cauchy matrix, using x_i = 2^-i, and y_i = 0 for i=0, and y_i = 2^i for other i.  In this case:   x = { 1, 142, 71, 173, 216, 108 }  y = { 0, 2, 4).  The cauchy matrix is:

Sorry, I took xi and yj to mean a constant x multiplied with i and a
constant y multiplied with j, rather than x_i and y_j.

	-hpa