Search: id:A101204 Results 1-1 of 1 results found. %I A101204 %S A101204 1,0,1,1,0,1,1,1,2,1,3,4,5,4,1,9,16,22,16,7,1,32,75,112,86,41,10,1,133 %N A101204 Triangle read by rows: T(n,k) = number of planar trivalent (or cubic) multigraphs with 2n nodes and exactly k double bonds, for 0 <= k <= n. %C A101204 The entries in the first two rows are "by convention". %D A101204 A. T. Balaban, Enumeration of Cyclic Graphs, pp. 63-105 of A. T. Balaban, ed., Chemical Applications of Graph Theory, Ac. Press, 1976; see p. 92. %e A101204 Triangle begins %e A101204 1 %e A101204 0 1 %e A101204 1 0 1 %e A101204 1 1 2 1 %e A101204 3 4 5 4 1 %e A101204 9 16 22 16 7 1 %e A101204 32 75 112 86 41 10 1 %e A101204 133 ... %Y A101204 Row sums give A005966. First column is A005964 (trivalent connected planar graphs with 2n nodes). Second and third columns give A101205, A101206. %Y A101204 Sequence in context: A088267 A117407 A082470 this_sequence A035043 A155963 A058684 %Y A101204 Adjacent sequences: A101201 A101202 A101203 this_sequence A101205 A101206 A101207 %K A101204 nonn,tabl %O A101204 0,9 %A A101204 N. J. A. Sloane (njas(AT)research.att.com), Dec 13 2004 Search completed in 0.001 seconds