I have done many examples with n-Clan and also with n-Clique, but I found an example online as shown in the figure bellow, it says there is only 1 2-Clan and also 1 2-Clique, nevertheless I think it is not only 1 2-Clan neither 1 2-Clique, because I see it has 2 2-Clan and also 2 2-Clique which are {243} and {124}, am I right ?
Thank you
Certainly if 124 is a $2$-clique, then 234 is also a $2$-clique since they are isomorphic. According the the link you previously gave that contained definitions of these terms: http://www.analytictech.com/networks/subgroup.htm, I don't understand why either of these is a $2$-clique since they are not maximal sets with the property. For example, the entire graph is a $2$-clique since the diameter of the graph is $2$.