Real Analysis Exchange

Points of Continuity, Quasicontinuity, Cliquishness, and Upper and Lower Quasicontinuity

Ján Borsík

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The quadruplet $(C(f), Q(f), E(f), A(f))$ is characterized, where $C(f)$, $Q(f)$, $E(f)$ and $A(f)$ are the sets of all continuity, quasicontinuity, upper and lower quasicontinuity and cliquishness points of a real function $f$ of real variable, respectively.

Article information

Real Anal. Exchange, Volume 33, Number 2 (2007), 339-350.

First available in Project Euclid: 18 December 2008

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 26A15: Continuity and related questions (modulus of continuity, semicontinuity, discontinuities, etc.) {For properties determined by Fourier coefficients, see 42A16; for those determined by approximation properties, see 41A25, 41A27}
Secondary: 54C08: Weak and generalized continuity 54C30: Real-valued functions [See also 26-XX]

continuity quasicontinuity cliquishness upper and lower quasicontinuity


Borsík, Ján. Points of Continuity, Quasicontinuity, Cliquishness, and Upper and Lower Quasicontinuity. Real Anal. Exchange 33 (2007), no. 2, 339--350.

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