grinpy.invariants.dsi.annihilation_number¶
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grinpy.invariants.dsi.
annihilation_number
(G)¶ Return the annihilation number of the graph.
The annihilation number of a graph G is defined as:
\[a(G) = \max\{t : \sum_{i=0}^t d_i \leq m\}\]where
\[{d_1 \leq d_2 \leq \cdots \leq d_n}\]is the degree sequence of the graph ordered in non-decreasing order and m is the number of edges in G.
Parameters: G (NetworkX graph) – An undirected graph. Returns: The annihilation number of the graph. Return type: int