The Chromatic Number of Joins of Signed Graphs
نویسندگان
چکیده
We introduce joins of signed graphs and explore the chromatic number all-positive all-negative joins. prove an analogue to theorem that join two equals sum their numbers. Given graphs, is usually less than numbers, by amount depends on new concept deficiency a signed-graph coloration.
منابع مشابه
The locating chromatic number of the join of graphs
Let $f$ be a proper $k$-coloring of a connected graph $G$ and $Pi=(V_1,V_2,ldots,V_k)$ be an ordered partition of $V(G)$ into the resulting color classes. For a vertex $v$ of $G$, the color code of $v$ with respect to $Pi$ is defined to be the ordered $k$-tuple $c_{{}_Pi}(v)=(d(v,V_1),d(v,V_2),ldots,d(v,V_k))$, where $d(v,V_i)=min{d(v,x):~xin V_i}, 1leq ileq k$. If distinct...
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let $f$ be a proper $k$-coloring of a connected graph $g$ and $pi=(v_1,v_2,ldots,v_k)$ be an ordered partition of $v(g)$ into the resulting color classes. for a vertex $v$ of $g$, the color code of $v$ with respect to $pi$ is defined to be the ordered $k$-tuple $c_{{}_pi}(v)=(d(v,v_1),d(v,v_2),ldots,d(v,v_k))$, where $d(v,v_i)=min{d(v,x):~xin v_i}, 1leq ileq k$. if distinct...
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ژورنال
عنوان ژورنال: Graphs and Combinatorics
سال: 2021
ISSN: ['1435-5914', '0911-0119']
DOI: https://doi.org/10.1007/s00373-021-02387-6