# Operational quantities characterizing semi-Fredholm operators

Manuel González; Antonio Martinón

Studia Mathematica (1995)

- Volume: 114, Issue: 1, page 13-27
- ISSN: 0039-3223

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topGonzález, Manuel, and Martinón, Antonio. "Operational quantities characterizing semi-Fredholm operators." Studia Mathematica 114.1 (1995): 13-27. <http://eudml.org/doc/216176>.

@article{González1995,

abstract = {Several operational quantities have appeared in the literature characterizing upper semi-Fredholm operators. Here we show that these quantities can be divided into three classes, in such a way that two of them are equivalent if they belong to the same class, and are comparable and not equivalent if they belong to different classes. Moreover, we give a similar classification for operational quantities characterizing lower semi-Fredholm operators.},

author = {González, Manuel, Martinón, Antonio},

journal = {Studia Mathematica},

keywords = {operational quantity; semi-Fredholm operator; upper semi-Fredholm operators; lower semi-Fredholm operators},

language = {eng},

number = {1},

pages = {13-27},

title = {Operational quantities characterizing semi-Fredholm operators},

url = {http://eudml.org/doc/216176},

volume = {114},

year = {1995},

}

TY - JOUR

AU - González, Manuel

AU - Martinón, Antonio

TI - Operational quantities characterizing semi-Fredholm operators

JO - Studia Mathematica

PY - 1995

VL - 114

IS - 1

SP - 13

EP - 27

AB - Several operational quantities have appeared in the literature characterizing upper semi-Fredholm operators. Here we show that these quantities can be divided into three classes, in such a way that two of them are equivalent if they belong to the same class, and are comparable and not equivalent if they belong to different classes. Moreover, we give a similar classification for operational quantities characterizing lower semi-Fredholm operators.

LA - eng

KW - operational quantity; semi-Fredholm operator; upper semi-Fredholm operators; lower semi-Fredholm operators

UR - http://eudml.org/doc/216176

ER -

## References

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