1,7
The smallest such graph is on 6 vertices, commonly called the "double gem."
Sequence in context: A198766 A204092 A020056 * A151330 A010913 A142988
Adjacent sequences: A086839 A086840 A086841 * A086843 A086844 A086845
nonn
Jim Nastos (nastos(AT)gmail.com), Aug 08 2003