Results 41 to 50 of about 60,649 (158)
Efficient enumeration of graceful permutations [PDF]
A graceful n-permutation is a graceful labeling of an n-vertex path P_n. In this paper we improve the asymptotic lower bound on the number of such permutations from (5/3)^n to 2.37^n. This is a computer-assisted proof based on an effective algorithm that enumerates graceful n-permutations. Our algorithm is also presented in detail.
arxiv
Graceful labelling of the union of paths and cycles
Frucht and Salinas (Ars. Combin. 20 (1985) 143–157) have proved that C4∪Pn is graceful, for every n⩾3, and they have conjectured that Cs∪Pn is graceful if n+s⩾7. In this paper we show that Cs∪Pn is graceful if s⩾5 and n⩾(s+5)/2.
Sheshayya A. Choudum+1 more
openaire +2 more sources
On alpha labeling of tensor product of paths and cycles. [PDF]
L U, G R.
europepmc +1 more source
Odd-graceful labelings of trees of diameter 5 [PDF]
A difference vertex labeling of a graph G is an assignment f of labels to the vertices of G that induces for each edge xy the weight |f(x)-f(y)|. A difference vertex labeling f of a graph G of size n is odd-graceful if f is an injection from V(G) to {0,1,...,2n-1} such that the induced weights are {1,3,...,2n-1}.
arxiv
A structural approach to the graceful coloring of a subclass of trees. [PDF]
D L, S DY.
europepmc +1 more source
On certain classes of graceful lobsters [PDF]
A graph G=(V,E) with m edges is graceful if it has a distinct vertex labeling f, a map from V into the set{0,1,2,3,...,m} which induces a distinct edge labeling |f(u)-f(v)| for edges uv in E. The famous Ringel-Kotzig conjecture (1964) is that all trees are graceful. The base of a tree T is obtained from T by deleting its one-degree vertices.
arxiv
A new graceful labeling for pendant graphs [PDF]
A graceful labeling of a graph G with q edges is an injective assignment of labels from {0, 1, . . . , q} to the vertices of G so that when each edge is assigned the absolute value of the difference of the vertex labels it connects, the resulting edge labels are distinct.
openaire +2 more sources
Graphic Groups, Graph Homomorphisms, and Graphic Group Lattices in Asymmetric Topology Cryptography. [PDF]
Zhao M, Wang H, Yao B.
europepmc +1 more source
Ladder and Subdivision of Ladder Graphs with Pendant Edges are Odd Graceful [PDF]
The ladder graph plays an important role in many applications as Electronics, Electrical and Wireless communication areas. The aim of this work is to present a new class of odd graceful labeling for the ladder graph. In particular, we show that the ladder graph Ln with m-pendant Ln + mk1 is odd graceful.
arxiv
Applying Skolem Sequences to Gracefully Label New Families of Triangular Windmills [PDF]
A function $f$ is a \textit{graceful labelling} of a graph $G=(V,E)$ with $m$ edges if $f$ is an injection $f:V\mapsto \{0,1,2,\dots,m\}$ such that each edge $uv \in E$ is assigned the label $|f(u)-f(v)|$, and no two edge labels are the same. If a graph G has a graceful labelling, we say that $G$ itself is graceful.
arxiv