Is there a recursive formulae to compute the edge chromatic polynomial of a graph? The following formulae is known for the vertex chromatic polynomial of a grapg $G$ $P(G,x)=P(G-uv, x)- P(G/uv,x)$ (See https://en.wikipedia.org/wiki/Chromatic_polynomial)
Note that by the formulae I do not mean using the above formuale for the line graph of the graph.
Actually I would like to compute the edge chromatic polynomial of all graphs with seven vertices and I could not compute some of them by MAPLE.