Volume 9 | Number 1 | Year 2014 | Article Id. IJMTT-V9P508 | DOI : https://doi.org/10.14445/22315373/IJMTT-V9P508
Here we denote a diameter six tree by (a0, a1, a2, . . ., am, b1, b2, . . . , bn, c1, c2, . . . , cr) , where a0 is the center of the tree; ai; i = 1, 2, . . . ,m, bj, j = 1, 2, . . . , n , and ck, k = 1, 2, . . . , r are the vertices of the tree adjacent to a0 , each ai is the center of a diameter four tree, each bj is the center of a star, and each ck is a pendant vertex. Here we give graceful labelings to some new classes of diameter six trees (a0,a1, a2, . . . , am, b1, b2, . . . , bn, c1, c2, . . . , cr) in which we nd diameter four trees consisting of four different combinations of odd, even, and pendant branches with the total number of branches odd. Here by a branch we mean a star, i.e. we call a star an odd branch if its center has an odd degree and an even branch if its center has an even degree.
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Debdas Mishra , Amaresh Chandra Panda , Rajani Ballav Dash, "A Class Of Diameter Six Trees with Graceful Labeling," International Journal of Mathematics Trends and Technology (IJMTT), vol. 9, no. 1, pp. 84-94, 2014. Crossref, https://doi.org/10.14445/22315373/IJMTT-V9P508