| Title: | Interpolation theorems for a family of spanning subgraphs (English) | 
| Author: | Zhou, Sanming | 
| Language: | English | 
| Journal: | Czechoslovak Mathematical Journal | 
| ISSN: | 0011-4642 (print) | 
| ISSN: | 1572-9141 (online) | 
| Volume: | 48 | 
| Issue: | 1 | 
| Year: | 1998 | 
| Pages: | 45-53 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | Let $G$ be a graph with order $p$, size $q$ and component number $\omega $. For each $i$ between $p - \omega $ and $q$, let ${\mathcal C}_{i}(G)$ be the family of spanning $i$-edge subgraphs of $G$ with exactly $\omega $ components. For an integer-valued graphical invariant $\varphi $, if $H \rightarrow H^{\prime }$ is an adjacent edge transformation (AET) implies $|\varphi (H) - \varphi (H^{\prime })| \le 1$, then $\varphi $ is said to be continuous with respect to AET. Similarly define the continuity of $\varphi $ with respect to simple edge transformation (SET). Let $M_{j}(\varphi )$ and $m_{j}(\varphi )$ be the invariants defined by $M_{j}(\varphi )(H) = \max _{T \in {\mathcal C}_{j}(H)} \varphi (T)$, $ m_{j}(\varphi )(H) = \min _{T \in {\mathcal C}_{j}(H)} \varphi (T) $. It is proved that both $M_{p - \omega }(\varphi )$ and $m_{p - \omega }(\varphi )$ interpolate over $\mathbf{{\mathcal C}_{i}(G)}$, $ p - \omega \le i \le q$, if $\varphi $ is continuous with respect to AET, and that $M_{j}(\varphi )$ and $m_{j}(\varphi )$ interpolate over $\mathbf{{\mathcal C}_{i}(G)}$, $p - \omega \le j \le i \le q$, if $\varphi $ is continuous with respect to SET. In this way a lot of known interpolation results, including a theorem due to Schuster etc., are generalized. (English) | 
| MSC: | 05C99 | 
| idZBL: | Zbl 0927.05076 | 
| idMR: | MR1614068 | 
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| Date available: | 2009-09-24T10:10:52Z | 
| Last updated: | 2020-07-03 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/127397 | 
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