The term "sun graph" has several differing definitions. ISGCI defines a (complete) 
-sun
graph as a graph on 
nodes (sometimes also known as a trampoline graph; Brandstädt et al. 1987,
p. 112) consisting of a central complete graph 
with an outer ring of 
vertices, each of which is joined to both endpoints of the
closest outer edge of the central core.
Wallis (2000), Anitha and Lekshmi (2008), and the American Institute of Mathematics use the term "
-sun"
graph to instead refer to the graph on 
vertices obtained by attaching 
pendant edges to a cycle graph 
. These graphs are referred to as "sunlet graphs" by ISGCI. The 3-sunlet graph 
is also known as the
net graph.
The sun graphs are pancyclic and uniquely Hamiltonian.
The bipartite double graph of the sun graph 
for 
odd is 
.
