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Near-rings with identity
Abbreviation: NRng1
Definition
A \emph{near-ring with identity} is a structure N=⟨N,+,−,0,⋅,1⟩ of type ⟨2,1,0,2,0⟩ such that
⟨N,+,−,0,⋅⟩ is a near-rings
1 is a \emph{multiplicative identity}: x⋅1=xand1⋅x=x
Morphisms
Let M and N be near-rings with identity. A morphism from M to N is a function h:M→N that is a homomorphism:
h(x+y)=h(x)+h(y), h(x⋅y)=h(x)⋅h(y), h(1)=1
Remark: It follows that h(0)=0 and h(−x)=−h(x).
Examples
Example 1: ⟨RR,+,−,0,⋅,1⟩, the near-ring of functions on the real numbers with pointwise addition, subtraction, zero, composition, and the identity function.
Basic results
0 is a zero for ⋅: 0⋅x=0 and x⋅0=0.
Properties
Finite members
f(1)=1f(2)=f(3)=f(4)=f(5)=f(6)=