Search: id:A067309 Results 1-1 of 1 results found. %I A067309 %S A067309 0,0,2,9,82,1607,95647 %N A067309 Number of symmetric unlabeled digraphs (unlabeled digraphs with nontrivial automorphism group). %F A067309 a(n)=A000273(n)-A051504(4) %e A067309 For n=4 nodes from the 218 (=A000273(4)) unlabeled nonisomorphic digraphs 136(=A051504(4)) are asymmetric, so 218-136=82 are somehow symmetric. %Y A067309 Cf. A000273, A051504. %Y A067309 Sequence in context: A117581 A123570 A006040 this_sequence A087798 A113146 A069234 %Y A067309 Adjacent sequences: A067306 A067307 A067308 this_sequence A067310 A067311 A067312 %K A067309 nonn %O A067309 0,3 %A A067309 Labos E. (labos(AT)ana.sote.hu), Jan 11 2002 Search completed in 0.001 seconds