Here is some information about the 11 graphs on 4 vertices,
keyed to the graph reference numbers employed by Peter Steinbach 
in his "Field Guide to Simple Graphs".  The vertices in each graph 
are labelled from 1 to 4.  Each line of the file corresponds
to a graph, and contains the following information:

(1) Steinbach's reference number for the graph.
(2) The degree sequence of the graph as a string of 4 digits, with the
    degree of vertex 4 first, then the degree of vertex 3, and so on down to
    the degree of vertex 1.
(3) The edge set of the graph, with each edge listed as the pair of
    digits corresponding to its two vertices.


Graph  1: |  Degree Sequence is  0000  | (no edges)
Graph  2: |  Degree Sequence is  0011  | Edge  12 
Graph  3: |  Degree Sequence is  0112  | Edges 12 13 
Graph  4: |  Degree Sequence is  1111  | Edges 12 34 
Graph  5: |  Degree Sequence is  0222  | Edges 12 13 23 
Graph  6: |  Degree Sequence is  1122  | Edges 12 13 24 
Graph  7: |  Degree Sequence is  1113  | Edges 12 13 14 
Graph  8: |  Degree Sequence is  2222  | Edges 12 13 24 34 
Graph  9: |  Degree Sequence is  1223  | Edges 12 13 14 23 
Graph 10: |  Degree Sequence is  2233  | Edges 12 13 14 23 24 
Graph 11: |  Degree Sequence is  3333  | Edges 12 13 14 23 24 34