A simple graph G is said to have property P k if it contains a complete subgraph of order k + 1, and a sequence Ο is potentially P k -graphical if it has a realization having property P k . Let Ο(k, n) denote the smallest degree sum such that every n-term graphical sequence Ο without zero terms and
Line-graphical degree sequences
β Scribed by Douglas Bauer
- Publisher
- John Wiley and Sons
- Year
- 1980
- Tongue
- English
- Weight
- 560 KB
- Volume
- 4
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
A degree sequence rr = (d,, d2, . . . , d,), with d, r d 2 r -* * 2 d,, is line graphical if it is realized by the line graph of some graph. Degree sequences with line-graphical realizations are characterized for the cases d, = p -I , d, = p -2, d, 5 3 , and d, = d,. It is also shown that if a degree sequence with d, = p -1 is line graphical, it is uniquely line graphical. It follows that with possibly one exception each line-graphical realization of an arbitrary degree sequence must have either C, , 2K, + K2, K, +2K2, or 3K, as an induced subgraph.
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