Conference Paper

On Noncrossing and Plane Tree-Like Structures

Volume: 4 Number: 2 June 30, 2021
EN

On Noncrossing and Plane Tree-Like Structures

Abstract

Mathematical trees are connected graphs without cycles, loops and multiple edges. Various trees such as Cayley trees, plane trees, binary trees, $d$-ary trees, noncrossing trees among others have been studied extensively. Tree-like structures such as Husimi graphs and cacti are graphs which posses the conditions for trees if, instead of vertices, we consider their blocks. In this paper, we use generating functions and bijections to find formulas for the number of noncrossing Husimi graphs, noncrossing cacti and noncrossing oriented cacti. We extend the work to obtain formulas for the number of bicoloured noncrossing Husimi graphs, bicoloured noncrossing cacti and bicoloured noncrossing oriented cacti. Finally, we enumerate plane Husimi graphs, plane cacti and plane oriented cacti according to number of blocks, block types and leaves.

Keywords

noncrossing tree , plane trees , tree-like structure , Husimi graph , cactus , enumeration

References

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APA
Okoth, I. O. (2021). On Noncrossing and Plane Tree-Like Structures. Communications in Advanced Mathematical Sciences, 4(2), 89-99. https://doi.org/10.33434/cams.803065
AMA
1.Okoth IO. On Noncrossing and Plane Tree-Like Structures. Communications in Advanced Mathematical Sciences. 2021;4(2):89-99. doi:10.33434/cams.803065
Chicago
Okoth, Isaac Owino. 2021. “On Noncrossing and Plane Tree-Like Structures”. Communications in Advanced Mathematical Sciences 4 (2): 89-99. https://doi.org/10.33434/cams.803065.
EndNote
Okoth IO (June 1, 2021) On Noncrossing and Plane Tree-Like Structures. Communications in Advanced Mathematical Sciences 4 2 89–99.
IEEE
[1]I. O. Okoth, “On Noncrossing and Plane Tree-Like Structures”, Communications in Advanced Mathematical Sciences, vol. 4, no. 2, pp. 89–99, June 2021, doi: 10.33434/cams.803065.
ISNAD
Okoth, Isaac Owino. “On Noncrossing and Plane Tree-Like Structures”. Communications in Advanced Mathematical Sciences 4/2 (June 1, 2021): 89-99. https://doi.org/10.33434/cams.803065.
JAMA
1.Okoth IO. On Noncrossing and Plane Tree-Like Structures. Communications in Advanced Mathematical Sciences. 2021;4:89–99.
MLA
Okoth, Isaac Owino. “On Noncrossing and Plane Tree-Like Structures”. Communications in Advanced Mathematical Sciences, vol. 4, no. 2, June 2021, pp. 89-99, doi:10.33434/cams.803065.
Vancouver
1.Isaac Owino Okoth. On Noncrossing and Plane Tree-Like Structures. Communications in Advanced Mathematical Sciences. 2021 Jun. 1;4(2):89-9. doi:10.33434/cams.803065