## Abstract __IPV__ is the intuitionistic theory axiomatized by Cook's equational theory __PV__ plus __PIND__ on __NP__‐formulas. Two extensions of __IPV__ were introduced by Buss and by Cook and Urquhart by adding __PIND__ for formulas of the form __A__(__x__) ∨ __B__, respectively ¬¬__A__(__x__),
On two questions about circular choosability
✍ Scribed by Serguei Norine
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 122 KB
- Volume
- 58
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
We answer two questions of Zhu on circular choosability of graphs. We show that the circular list chromatic number of an even cycle is equal to 2 and give an example of a graph for which the infimum in the definition of the circular list chromatic number is not attained. © 2008 Wiley Periodicals, Inc. J Graph Theory 58:261‐269, 2008
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