From 943f359df5dc8cbc4913191125c708a8d4b3a9b2 Mon Sep 17 00:00:00 2001 From: Simone Bovi Date: Sat, 18 Jan 2020 12:46:16 +0100 Subject: [PATCH] Add specification about singular case --- ch01.asciidoc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ch01.asciidoc b/ch01.asciidoc index 22540968..cfc8da67 100644 --- a/ch01.asciidoc +++ b/ch01.asciidoc @@ -509,7 +509,7 @@ include::code-ch01/answers.py[tag=exercise5,indent=0] [NOTE] ==== The answer to Exercise 5 is why we choose to use finite fields with a _prime_ number of elements. -No matter what _k_ you choose, as long as it's greater than 0, multiplying the entire set by _k_ will result in the same set as you started with. +No matter what _k_ you choose, as long as it's greater than 0 (and different from the order of the set), multiplying the entire set by _k_ will result in the same set as you started with. Intuitively, the fact that we have a prime order results in every element of a finite field being equivalent. If the order of the set was a composite number, multiplying the set by one of the divisors would result in a smaller set.