Definitions
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun mathematics, countable The least of the
cardinalities of thecofinal subsets of apartially ordered set .
Etymologies
Sorry, no etymologies found.
Support
Help support Wordnik (and make this page ad-free) by adopting the word cofinality.
Examples
-
"cofinality" of the ordinal, which I had not heard of before.
-
"cofinality" of the ordinal, which I had not heard of before.
Planet Haskell 2008
-
What is the cofinality of the wellordering of the ordinals?
Quine's New Foundations Forster, Thomas 2006
-
So, for example, the cofinality of ω is ℵ 0, or, in the language of order types,
Planet Haskell 2008
-
The cofinality of S is the minimum cardinality of its cofinal subsets, or, what is pretty much the same thing, the minimum order type of its cofinal subsets.
Planet Haskell 2008
-
My question, phrased in terms of cofinality, is simply whether any ordinal has uncountable cofinality.
Planet Haskell 2008
-
And yet it has countable cofinality, as witnessed by the limiting sequence I just gave.
Planet Haskell 2008
-
My question, phrased in terms of cofinality, is simply whether any ordinal has uncountable cofinality.
-
But some uncountable ordinals have countable cofinality.
Planet Haskell 2008
-
But the cofinality of ω + 1 is only 1 (because the subset {ω} is cofinal), as is the confinality of any successor ordinal.
Planet Haskell 2008
Comments
Log in or sign up to get involved in the conversation. It's quick and easy.