|
%I #15 May 13 2017 17:47:55
%S 1,1,2,2,2,3,3,4,3,5,4,5,6,6,5,7,5,8,8,8,6,11,8,10,9,11,8,13,8,12,12,
%T 13,12,15,10,14,14,17,11,18,11,17,17,17,12,21,14,20,18,20,14,22,18,23,
%U 20,22,15,27,16,23,23,24,22,28,17,26,24,29,18,31,19,28,28,29,24,33,20
%N Number of nonisomorphic generalized Petersen P(n,k) graphs on 2n nodes for 1<=k<=floor((n-1)/2).
%C A generalized Petersen graph P(n,k) has 2n nodes and 3n edges and consists of an outer n-gon and an inner {n,k} star polygon for some k in the range 1<=k<=floor((n-1)/2); sequence gives number of nonisomorphic generalized Petersen graphs P(n,k) (for any k).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GeneralizedPetersenGraph.html">Generalized Petersen Graph</a>
%e The generalized Petersen graphs P(22,k) for k = 1, 2, 3, 4, 5, 6, 8, 10 are pairwise nonisomorphic, so a(22) = 8. - Arjana Zitnik (Arjana.Zitnik(AT)fmf.uni-lj.si)
%t CountDistinct /@ Table[CanonicalGraph[PetersenGraph[n, k]], {n, 3, 79}, {k, (n - 1)/2}] (* _Eric W. Weisstein_, May 13 2017 *)
%K nonn
%O 3,3
%A _Eric W. Weisstein_, Oct 28 2002
%E My colleague Arjana Zitnik (Arjana.Zitnik(AT)fmf.uni-lj.si) found that a(22) was wrong. - _Tomaz Pisanski_, Nov 23 2004
%E Sequence corrected and extended by _Eric W. Weisstein_, Nov 28 2004
|
