Re:Do we have negative prime numbers?
by wodenokoto on Saturday January 16, 2021 @12:17PM
(#25803609)
In this context, what is a ring?
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https://en.m.wikipedia.org/wiki/Ring_(mathematics) it’s a little hard to describe as it’s fairly abstract.
It’s a structure that is subset of abelian groups (groups where operations on elements of the group don’t depend on the order written, ie x+y = y+x).
For example the set of ints with “normal” addition and multiplication is a communicative ring
A number system with a notion of addition and multiplication. Examples are the integers, rationals, complex numbers, polynomials over any of the above, and so on.
From a programming point of view, imagine a type with an overloaded + and * operator. You'll be close.
A set equipped with operations addition , negation, multiplication, and often a 1 as an identity element of the multiplication, where the addition is associative and commutative and has the negation as its inverse, and the multiplication distributed over the addition. Sometimes people don’t always require that they include a unit for the multiplication.
An example of a ring is the set of integers, as is the set of integers mod 6, as is any field. A non-example is the set of non-negative integers.