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-rw-r--r--src/doc/en/constructions/linear_codes.rst12
1 files changed, 9 insertions, 3 deletions
diff --git a/src/doc/en/constructions/linear_codes.rst b/src/doc/en/constructions/linear_codes.rst
index b11e17e..fe4d018 100644
--- a/src/doc/en/constructions/linear_codes.rst
+++ b/src/doc/en/constructions/linear_codes.rst
@@ -195,7 +195,8 @@ pseudo-random. {pseudo-random}
A general feedback shift register is a map
:math:`f:{\bf F}_q^d\rightarrow {\bf F}_q^d` of the form
-.. math::
+.. MATH::
+
\begin{array}{c}
f(x_0,...,x_{n-1})=(x_1,x_2,...,x_n),\\
x_n=C(x_0,...,x_{n-1}),
@@ -205,13 +206,17 @@ A general feedback shift register is a map
where :math:`C:{\bf F}_q^d\rightarrow {\bf F}_q` is a given
function. When :math:`C` is of the form
-..math:: C(x_0,...,x_{n-1})=c_0x_0+...+c_{n-1}x_{n-1},
+.. MATH::
+
+ C(x_0,...,x_{n-1}) = c_0 x_0 + ... + c_{n-1} x_{n-1},
for some given constants :math:`c_i\in {\bf F}_q`, the map is
called a linear feedback shift register (LFSR). The sequence of
coefficients :math:`c_i` is called the key and the polynomial
-.. math::C(x) = 1+ c_0x +...+c_{n-1}x^n
+.. MATH::
+
+ C(x) = 1+ c_0x +...+c_{n-1}x^n
.. index::
pair: ciphers; connection polynomial
@@ -229,6 +234,7 @@ Example: Over :math:`GF(2)`, if
The LFSR sequence is then
.. math::
+
\begin{array}{c}
1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, \\
1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, ...\ .