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TOTAL PATHOS TOTAL VERTEX SEMIENTIRE BLOCK GRAPH
VENKANAGOUDA M GOUDAR
1
, RAJANNA N E
2
& C K SUBBARAYA
3
1
Department of Mathematics, Sri Siddhartha Institute of Technology, Tumkur, Karnataka, India
2
Research scholar Sri Siddhartha Academy of Higher Education, Tumkur, Department of Mathematics,
Adichunchanagiri Institute of Technology, Chikmagalur, Karnataka, India
3
Department of Computer Science and Engineering, Adichunchanagiri Institute of Technology,
Chikmagalur, Karnataka, India
ABSTRACT
In this paper, we introduce the concept of total pathos total vertex semientire block graph of a tree. We obtain
some properties of this graph. We study the characterization of graphs whose of total pathos total vertex semientire block
graph of a tree is Hamiltonian, nonplanar and noneulerian.
KEYWORDS: Block Graph, Inner Vertex Number, Line Graph, Path of Pathos, Vertex Semientire Graph
Mathematics Subject Classification: 05C
1. INTRODUCTION
All graphs considered here are finite, undirected without loops or multiple edges. Any undefined term or notation
in this paper may be found in Harary [2].
The concept of pathos of a graph G was introduced by Harary [2], as a collection of minimum number of line
disjoint open paths whose union is G. The path number of a graph G is the number of paths in pathos.
For a graph G(p, q) if B = { u
1
, u
2
, u
3
, · · · , u
r
; r ≥2} is a block of G , then we say that point u
1
and block B are
incident with each other, as are u
2
and B and so on. If two distinct blocks B
1
and B
2
are incident with a common cut vertex
then they are called adjacent blocks.
By a plane graph G we mean embedded in the plane as opposed to a planar graph. In a plane graph G, let e
1
={u,v
}be an edge. We say e
1
is adjacent to the vertices u and v, which are also adjacent to each other. Also an edge e
1
is adjacent
to the edge e
2
=uw. A region of G is adjacent to the vertices and edges which are on its boundary, and two regions of G are
adjacent if their boundaries share a common vertex.
The edgedegree of an edge e = {a, b} is the sum of degrees of the end vertices a and b. Degree of a block is the
number of vertices lies on a block. Blockdegree B
v
of a vertex v is the number of blocks in which v lies. Degree of a region
is the number of vertices lies on a region. The regiondegree R
v
of a vertex v is the number of regions in which the vertex v
lies.
A new concept of a graph valued functions called the vertex semientire block graph e
vb
(G) of a plane graph G was
introduced by Venkanagouda in [9] and is defined as the graph whose vertex set is the union of the set of vertices, blocks
International Journal of Applied Mathematics
& Statistical Sciences (IJAMSS)
ISSN(P): 2319-3972; ISSN(E): 2319-3980
Vol. 5, Issue 3, Apr - May 2016; 53-62
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