in this paper we give sharp upper bounds on the zagreb indices and characterize all trees achieving equality in these bounds. also, we give lower bound on first zagreb coindex of trees.

we give sharp upper bounds on the zagreb indices and lower bounds on the zagreb coindices of chemical trees and characterize the case of equality for each of these topological invariants.

The need to generate graphs representing chemical structures suggested the use of computer and as a consequence the delevopment of eecient enumerating algorithms. This paper considers the isomeric acyclic structures enumeration focusin on the alkane molecular family. Two new algorithms based on Reverse Search 7] 8] are presented. The main concern of this paper is to highlight the importance of ...

classification trees (j48) were induced to predict the habitat requirements of tench (tinca tinca). 306 datasets were used for the given fish during 8 years in the river basins in flanders (belgium). the input variables consisted of the structural-habitat (width, depth, gradient slope and distance from the source) and physic chemical (ph, dissolved oxygen, water temperature and electric conduct...

in order to investigate some silvicultural and soil physico-chemical characteristics of christ's thorn (ziziphus spina christi l. desf.) natural stands, ten natural stands of the tree species which have similar climate and aspects were selected and altitude from sea level (asl), the thickest sprout collar diameter (tscd) and total tree height (th) of the tree species were measured in 1000 ...