In Sage v8.6, the output of the function:
Graph([[1,1]],multiedges=True,loops=True).chromatic_polynomial()
is:
x
but it seems to me that, if graphs with loops are allowed, it should be:
0
as there are no proper colorings of graphs with loops.
1 | initial version |
In Sage v8.6, the output of the function:
Graph([[1,1]],multiedges=True,loops=True).chromatic_polynomial()
is:
x
but it seems to me that, if graphs with loops are allowed, it should be:
0
as there are no proper colorings of graphs with loops.
In Sage v8.6, the output of the function:
Graph([[1,1]],multiedges=True,loops=True).chromatic_polynomial()
is:
x
but it seems to me that, if graphs with loops are allowed, it should be:
0
as Since there are no proper colorings of graphs with loops. loops,
their chromatic polynomial should be zero.
SageMath 8.6 however seems to ignore the loops and returns a nonzero chromatic polynomial for the graph on one vertex with one loop edge.
sage: Graph([[1, 1]], multiedges=True, loops=True).chromatic_polynomial()
x
3 | retagged |
Since there are no proper colorings of graphs with loops, their chromatic polynomial should be zero.
SageMath 8.6 however seems to ignore the loops and returns a nonzero chromatic polynomial for the graph on one vertex with one loop edge.
sage: Graph([[1, 1]], multiedges=True, loops=True).chromatic_polynomial()
x
4 | retagged |
Since there are no proper colorings of graphs with loops, their chromatic polynomial should be zero.
SageMath 8.6 however seems to ignore the loops and returns a nonzero chromatic polynomial for the graph on one vertex with one loop edge.
sage: Graph([[1, 1]], multiedges=True, loops=True).chromatic_polynomial()
x