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An inner automorphism, Inn(G), is always attached to some group element written ϕ_{a} for the following morphism from G to itself: ϕ_{a}(g)=aga⁻¹ | An inner automorphism, Inn(G), is always attached to some group element written ϕ_{a} for the following morphism from G to itself: ϕ_{a}(g)=aga⁻¹ | ||
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| + | If m and n are coprime, then Z_mn is isomorphic to Z_m x Z_n | ||
Revision as of 12:15, 24 February 2009
Euclid
a = qb + r with 0 <= r < b
where a,b,q,r are integers
--ERaymond 12:26 29 January 2009 (UTC)
GCD: The greatest common divisor of two nonzero integers a and b is the largest of all common divisors of a and b.
LCM: The least common multiple of two nonzero integers a and b is the smallest positive integer that is a multiple of both a and b.
--Jmcdorma 12:16, 5 February 2009 (UTC)
Monomorphism: morphism for which phi(g) = phi(g') happens only if g = g'. (injective)
Epimorphism: morphism for which every element in target group H is hit. (surjective)
Isomorphism: morphism that is both injective and surjective.
The kernel of a morphism is the collection of elements in G that satisfy phi(g) = 1_H
An inner automorphism, Inn(G), is always attached to some group element written ϕ_{a} for the following morphism from G to itself: ϕ_{a}(g)=aga⁻¹
If m and n are coprime, then Z_mn is isomorphic to Z_m x Z_n
