Neha Patil (Editor)

Almost convergent sequence

Updated on
Edit
Like
Comment
Share on FacebookTweet on TwitterShare on LinkedInShare on Reddit

A bounded real sequence ( x n ) is said to be almost convergent to L if each Banach limit assigns the same value L to the sequence ( x n ) .

Lorentz proved that ( x n ) is almost convergent if and only if

lim p → ∞ x n + … + x n + p − 1 p = L

uniformly in n .

The above limit can be rewritten in detail as

( ∀ ε > 0 ) ( ∃ p 0 ) ( ∀ p > p 0 ) ( ∀ n ) | x n + … + x n + p − 1 p − L | < ε .

Almost convergence is studied in summability theory. It is an example of a summability method which cannot be represented as a matrix method.

References

Almost convergent sequence Wikipedia


Similar Topics
×