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Galois Field Arithmetic

Galois Fields = fields of finite order (cardinality).
Notation: GF(q) = Galois field of order q.

Theorem: The integers tex2html_wrap_inline286 where p is a prime, form the field GF(p) under modulo p addition and multiplication.

Definition: Let tex2html_wrap_inline292 be an element in GF(q). The order of tex2html_wrap_inline292 is the smallest positive integer m such that tex2html_wrap_inline300 .

Theorem: If tex2html_wrap_inline302 for some tex2html_wrap_inline304 , then tex2html_wrap_inline306 .

Definition: An element with order (q-1) in GF(q) is called a primitive element in GF(q).

Every field GF(q) contains at least one primitive element tex2html_wrap_inline316 .
All nonzero elements in GF(q) can be represented as (q-1) consecutive powers of a primitive element tex2html_wrap_inline322

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Theorem: The order q of a Galois Field GF(q) must be a power of a prime.





A. Matache
Sun Oct 20 17:42:25 PDT 1996