On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle CAUCHY –Jurnal Matematika Murni dan Aplikasi Volume 6(1) (2019), Pages 40-48 p-ISSN: 2086-0382; e-ISSN: 2477-3344 Submitted: November 19, 2019 Reviewed: November 26, 2019 Accepted: November 30, 2019 DOI: http://dx.doi.org/10.18860/ca.v6i1.8054 On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah1, Ridho Alfarisi3, Rafiantika M. Prihandini2, Arika Indah Kristiana2, Ratna Dwi C.1 1Mathematics Department, Kaltara University of North Kalimantan 2 Mathematics Education Department, Jember University of Jember 3 Primary School Department, Jember University of Jember Email: aisyah_rasyid84@yahoo.com, alfarisi.fkip@unej.ac.id, arikakristiana@gmail.com, r_christyanti@yahoo.com ABSTRACT Let 𝐺(𝑉,𝐸) be a nontrivial and connected graph of vertex set 𝑉 and edge set 𝐸. A bijection 𝑓:𝑉(𝐺) β†’ {1,2,3,…,|𝑉(𝐺)|} is called a local edge antimagic labeling if for any two adjacent edges 𝑒1 and 𝑒2,𝑀(𝑒1) β‰  𝑀(𝑒2), where 𝑒 = 𝑒𝑣 ∈ 𝐸(𝐺),𝑀(𝑒) = 𝑓(𝑒) + 𝑓(𝑣). Thus, the local edge antimagic labeling induces a proper edge coloring of 𝐺 if each edge 𝑒 assigned the color 𝑀(𝑒). The color of any edge 𝑒 = 𝑒𝑣 is assigned by 𝑀(𝑒) which is defined by the sum of both vertices labels 𝑓(𝑒) and 𝑓(𝑣). The local edge antimagic chromatic number, denoted by π›Ύπ‘™π‘Žπ‘’(𝐺) is the minimum number of colors taken over all colorings induced by local edge antimagic labeling of 𝐺. In our paper, we present the local edge antimagic coloring of corona product of path and cycle, namely path corona cycle, cycle corona path, path corona path, and cycle corona cycle. Keywords: Local antimagic; edge coloring; corona product; path; cycle. INTRODUCTION The local antimagic vertex coloring of a graph 𝐺 introduced by Arumugam et. al [1]. Furthermore, Agustin, et. al [2] defined local edge antimagic coloring of the graph. A bijection 𝑓:𝑉(𝐺) β†’ {1,2,3, . . . , |𝑉(𝐺)|}, is called a local edge antimagic labeling if every two adjacent edges 𝑒1 and 𝑒2, 𝑀(𝑒1) β‰  𝑀(𝑒2), where 𝑒 = 𝑒𝑣 ∈ 𝐸(𝐺), and 𝑀(𝑒) = 𝑓(𝑒) + 𝑓(𝑣). Thus, the local edge antimagic labeling induces a proper edge coloring of 𝐺 if any edge 𝑒 is assigned the color 𝑀(𝑒). The color of each edge 𝑒 = 𝑒𝑣 are assigned by 𝑀(𝑒) which is defined by the sum of label both and vertices 𝑓(𝑒) and 𝑓(𝑣). The local edge antimagic chromatic number, denoted by π›Ύπ‘™π‘Žπ‘’(𝐺), is the minimum number of colors taken over all colorings induced by local edge antimagic labeling of graph 𝐺. Agustin, et. al [2] establish the local edge antimagic chromatic number of path graph and cycle graph. Dettlaff, et. al in [3], a corona graph of 𝐺 and 𝐻, denoted by 𝐺 βŠ™ 𝐻, is obtained by joining each vertex of Hi to the vertex uj of G. Ramya in [4], discussed an acyclic coloring of a corona graph and Yero in [5] studied coloring, location, and domination of a corona graph. Kristiana, et.al in [6] found the lower bound of the r-dynamic chromatic number of a corona product by wheel graphs. Many papers presented a corona product topics for example in [7], [2], and [8]. However, the local edge antimagic coloring of corona product still has nothing to discuss. In our paper, we investigate the local edge antimagic coloring of corona product of path and cycle, namely http://dx.doi.org/10.18860/ca.v6i1.8054 mailto:aisyah_rasyid84@yahoo.com mailto:alfarisi.fkip@unej.ac.id mailto:arikakristiana@gmail.com mailto:r_christyanti@yahoo.com On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 41 path corona cycle, cycle corona path, path corona path, and cycle corona cycle. The results of local edge antimagic labeling are as follows. Conjecture 1.1. Every connected graph other than 𝐾2 is local antimagic. Observation 1.1. [6]For any graph 𝐺, π›Ύπ‘™π‘Žπ‘’(𝐺) β‰₯ 𝛾(𝐺) βˆ’ 1. Observation 1.2. [8]For any graph G, Ο‡la(G) β‰₯ Ο‡(G), where Ο‡(G) is a vertex chromatic number of G. Observation 1.3. [6] For any graph 𝐺, π›Ύπ‘™π‘Žπ‘’(𝐺) β‰₯ 𝛾(𝐺), where 𝛾(𝐺) is an edge chromatic number of G. Theorem 1.1. [6] If Ξ”(𝐺) is maximum degrees of 𝐺, then we have π›Ύπ‘™π‘Žπ‘’(𝐺) β‰₯ Ξ”(𝐺). Proposition 1.1. [6] Let G be a connected graph, we have a) If 𝐺 β‰… 𝑃𝑛 , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 2. b) If 𝐺 β‰… 𝐢𝑛 , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 3. c) If 𝐺 β‰… 𝐿𝑛 , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 3. d) If 𝐺 β‰… 𝐾𝑛 , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 2𝑛 βˆ’ 3. e) If 𝐺 β‰… π‘Šπ‘› , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 𝑛 + 2. f) If 𝐺 β‰… 𝑆𝑛 , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 𝑛. g) If 𝐺 β‰… 𝐹𝑛 , then π›Ύπ‘™π‘Žπ‘’(𝐺) = 2𝑛 + 1. h) If 𝐺 βŠ™ π‘šπΎ1, then π›Ύπ‘™π‘Žπ‘’(𝐺 βŠ™ π‘šπΎ1) = π›Ύπ‘™π‘Žπ‘’(𝐺) + π‘š. RESULTS AND DISCUSSION In our paper, we consider the local edge antimagic chromatic number of a corona product of path and cycle, including path corona cycle, cycle corona path, path corona path, cycle corona cycle. Furthermore, we determine the exact values of local edge antimagic chromatic number of corona product in the following theorems. Theorem 2.1. The local edge antimagic chromatic number of 𝑃𝑛 βŠ™ π‘ƒπ‘š for 𝑛 odd and 𝑛,π‘š β‰₯ 3 is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ π‘ƒπ‘š) = 2(𝑛 + 1) + π‘š. Proof. The graph 𝑃𝑛 βŠ™ π‘ƒπ‘š is a connected graph with vertex set 𝑉(𝑃𝑛 βŠ™ π‘ƒπ‘š) = {π‘₯𝑖:1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑗 𝑖:1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛 } and edge set 𝐸(𝑃𝑛 βŠ™ π‘ƒπ‘š) = {π‘₯𝑖π‘₯𝑖+1:1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1} βˆͺ {π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 : 1 ≀ 𝑗 ≀ π‘š βˆ’ 1; 1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑖π‘₯𝑗 𝑖: 1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛}. The cardinality of the vertex set is |𝑉(𝑃𝑛 βŠ™ π‘ƒπ‘š)| = 𝑛 + π‘šπ‘› and the cardinality of the edge set is |𝐸(𝑃𝑛 βŠ™ π‘ƒπ‘š)| = 2π‘šπ‘› βˆ’ 1. We define a bijection 𝑓:𝑉(𝑃𝑛 βŠ™ π‘ƒπ‘š) β†’ {1,2,3,…, |𝑉(𝑃𝑛 βŠ™ π‘ƒπ‘š)|} for the graph 𝑃𝑛 βŠ™ π‘ƒπ‘š to be local edge antimagic labeling as follows. 𝑓(π‘₯𝑖) = { 𝑖 + 1 2 , if 𝑖 is odd 𝑛 βˆ’ ( 𝑖 βˆ’ 2 2 ), if 𝑖 is even On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 42 𝑓(π‘₯𝑗 𝑖) = { 𝑛 + 1 + ( 𝑖 βˆ’ 2 2 ) + ( 𝑗 βˆ’ 2 2 )𝑛, if 𝑖 and 𝑗 are even 2𝑛 + π‘›βŒˆ π‘š 2 βŒ‰ + 1 + ( 𝑖 βˆ’ 2 2 ) βˆ’ 𝑛( 𝑗 βˆ’ 1 2 ), if 𝑖 is even and 𝑗 is odd 2𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) + ( 𝑗 βˆ’ 2 2 )𝑛, if 𝑖 is odd and 𝑗 is even π‘šπ‘› + 𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) βˆ’ 𝑛( 𝑗 βˆ’ 1 2 ), if 𝑖 and 𝑗 are odd It is clear that 𝑓 is a local antimagic labeling of 𝑃𝑛 βŠ™ π‘ƒπ‘š and the edge weights are as follows: 𝑀(π‘₯𝑖π‘₯𝑖+1) = { 𝑛 + 1, if 𝑖 is odd 𝑛 + 2, if 𝑖 is even 𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) = { π‘šπ‘› + 3𝑛 βˆ’ (𝑖 βˆ’ 1), if 𝑖 and j are odd π‘šπ‘› + 2𝑛 βˆ’ (𝑖 βˆ’ 1), if 𝑖 is odd and 𝑗 is even π‘šπ‘› + 𝑛 + 𝑖, if 𝑖 is even and 𝑗 is odd π‘šπ‘› + 𝑖, if 𝑖 and 𝑗 are even 𝑀(π‘₯𝑖π‘₯𝑗 𝑖) = { π‘šπ‘› + 1 + 𝑛( 𝑗 βˆ’ 3 2 ), if 𝑗 is odd 2𝑛 + 1 + 𝑛( 𝑗 βˆ’ 2 2 ), if 𝑗 is even Hence, we get that the upper bound of the local edge antimagic chromatic number of 𝑃𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ π‘ƒπ‘š) ≀ 2(𝑛 + 1) + π‘š. Furthermore, we prove that lower bound of the local edge antimagic chromatic number of 𝑃𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ π‘ƒπ‘š) β‰₯ 2(𝑛 + 1) + π‘š. By contradiction, we assume that π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ π‘ƒπ‘š) < 2(𝑛 + 1) + π‘š. Without lost of generality, we assume that 𝑀(π‘₯𝑖π‘₯𝑖+1) β‰  𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) β‰  𝑀(π‘₯𝑖π‘₯𝑗 𝑖). Based on Proposition 1, π›Ύπ‘™π‘Žπ‘’(𝑃𝑛) = 2 and π›Ύπ‘™π‘Žπ‘’(π‘ƒπ‘š) = 2 then we get |{𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛)}| = 2, |{𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 )}| = π‘š and |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| = 2(𝑛 βˆ’ 1), |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑛)}| = 1 such that |𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛 βŠ™ π‘ƒπ‘š )| = |{𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛)}| +|{𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 )}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑛)}| |𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛 βŠ™ π‘ƒπ‘š )| = 2 + π‘š + 2(𝑛 βˆ’ 1) + 1 |𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛 βŠ™ π‘ƒπ‘š )| = π‘š + 2𝑛 + 1 If |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑛)}| = 1, then we obtain at least two edges which have same edge weight, it is a contradiction. Thus, we receive that the lower bound of the local edge antimagic chromatic number of 𝑃𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ π‘ƒπ‘š) β‰₯ π‘š + 2𝑛 + 2 = 2(𝑛 + 1) + π‘š. It concludes that the local antimagic edge chromatic number of 𝑃𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ π‘ƒπ‘š) = 2(𝑛 + 1) + π‘š.∎ Theorem 2.2 The local edge antimagic chromatic number of 𝑃𝑛 βŠ™ πΆπ‘š for 𝑛,π‘š odd and 𝑛,π‘š β‰₯ 4 is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ πΆπ‘š) = 2 + 3𝑛 + π‘š. Proof. The graph 𝑃𝑛 βŠ™ πΆπ‘š is a connected graph with vertex set 𝑉(𝑃𝑛 βŠ™ πΆπ‘š) = {π‘₯𝑖:1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑗 𝑖:1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛 } and edge set 𝐸(𝑃𝑛 βŠ™ πΆπ‘š) = {π‘₯𝑖π‘₯𝑖+1:1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1} βˆͺ {π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 : 1 ≀ 𝑗 ≀ π‘š βˆ’ 1; 1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯π‘š 𝑖 π‘₯1 𝑖 ,1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑖π‘₯𝑗 𝑖: 1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛}. The cardinality of the vertex set is |𝑉(𝑃𝑛 βŠ™ πΆπ‘š)| = 𝑛 + π‘šπ‘› and the cardinality of the edge set is |𝐸(𝑃𝑛 βŠ™ πΆπ‘š)| = 2π‘šπ‘› + 𝑛 βˆ’ 1. We define a function bijection 𝑓:𝑉(𝑃𝑛 βŠ™ πΆπ‘š) β†’ {1,2,3,…,|𝑉(𝑃𝑛 βŠ™ πΆπ‘š)|} for the graph 𝑃𝑛 βŠ™ πΆπ‘š to be local edge antimagic labeling as follows. On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 43 𝑓(π‘₯𝑖) = { 𝑖 + 1 2 , if 𝑖 is odd 𝑛 βˆ’ 𝑖 βˆ’ 2 2 , if 𝑖 is even 𝑓(π‘₯𝑗 𝑖) = { π‘šπ‘› + 1 + ( 𝑖 βˆ’ 2 2 ) βˆ’ ( 𝑗 βˆ’ 2 2 )𝑛, if 𝑖 and 𝑗 are even 𝑛 + 1 + ( 𝑖 βˆ’ 2 2 ) + ( 𝑗 βˆ’ 1 2 )𝑛, if 𝑖 is even and 𝑗 is odd π‘šπ‘› + 𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) βˆ’ ( 𝑗 βˆ’ 2 2 )𝑛, if 𝑖 is odd and 𝑗 is even 2𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) + 𝑛( 𝑗 βˆ’ 1 2 ), if 𝑖 and 𝑗 are odd 𝑓(π‘₯π‘š 𝑖 ) = { π‘›βŒˆ π‘š 2 βŒ‰ + 𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ), if 𝑖 is odd π‘›βŒˆ π‘š 2 βŒ‰ + 1 + ( 𝑖 βˆ’ 2 2 ), if 𝑖 is even It is easy to see that 𝑓 is a local edge antimagic labeling of 𝑃𝑛 βŠ™ πΆπ‘š and the edge weights are as follows: 𝑀(π‘₯𝑖π‘₯𝑖+1) = { 𝑛 + 1, if 𝑖 is odd 𝑛 + 2, if 𝑖 is even 𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) = { π‘šπ‘› + 4𝑛 βˆ’ (𝑖 βˆ’ 1), if 𝑖 and 𝑗 are odd π‘šπ‘› + 3𝑛 βˆ’ (𝑖 βˆ’ 1), if 𝑖 is odd and 𝑗 is even π‘šπ‘› + 2(𝑛 + 1) + (𝑖 βˆ’ 2), if 𝑖 is even and 𝑗 is odd π‘šπ‘› + 𝑛 + 2 + (𝑖 βˆ’ 2), if 𝑖 and 𝑗 are even 𝑀(π‘₯π‘š 𝑖 π‘₯1 𝑖) = { π‘›βŒˆ π‘š 2 βŒ‰ + 3𝑛 βˆ’ (𝑖 βˆ’ 1), if 𝑗 is odd π‘›βŒˆ π‘š 2 βŒ‰+ 𝑛 + 2 + (𝑖 βˆ’ 2), if 𝑗 is even 𝑀(π‘₯𝑖π‘₯𝑗 𝑖) = { 2𝑛 + 1 + 𝑛( 𝑗 βˆ’ 1 2 ), if 𝑗 is odd π‘šπ‘› + 𝑛 βˆ’ 𝑛( 𝑗 βˆ’ 2 2 ), if 𝑗 is even 𝑀(π‘₯𝑖π‘₯π‘š 𝑖 ) = { π‘›βŒˆ π‘š 2 βŒ‰+ 𝑛 + 1 βˆ’ ( 𝑖 βˆ’ 1 2 ), if 𝑗 is odd π‘›βŒˆ π‘š 2 βŒ‰ + 2 + ( 𝑖 βˆ’ 2 2 ), if 𝑗 is even Hence, we get that the upper bound of the local edge antimagic chromatic number of 𝑃𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ πΆπ‘š) ≀ 2 + 3𝑛 + π‘š. Furthermore, we prove that the lower bound of the On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 44 local edge antimagic chromatic number of 𝑃𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ πΆπ‘š) β‰₯ 2 + 3𝑛 + π‘š. By contradiction, we assume that π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ πΆπ‘š) < 2 + 3𝑛 + π‘š . Without of generality, 𝑀(π‘₯𝑖π‘₯𝑖+1) β‰  𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) β‰  𝑀(π‘₯1 𝑖π‘₯π‘š 𝑖 ) β‰  𝑀(π‘₯𝑖π‘₯𝑗 𝑖). Based on Proposition 1 that π›Ύπ‘™π‘Žπ‘’(𝑃𝑛) = 2 and π›Ύπ‘™π‘Žπ‘’(πΆπ‘š) = 3 then we get |{𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛)}| = 2, |{𝑀(π‘₯𝑖π‘₯𝑗 𝑖)}| = π‘š and |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| = 3(𝑛 βˆ’ 1), |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑛)}| = 2 such that |𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛 βŠ™ πΆπ‘š )| = |{𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛)}| + |{𝑀(π‘₯𝑖π‘₯𝑗 𝑖)}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}|+|{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑛)}| |𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛 βŠ™ πΆπ‘š )| = 2 + π‘š + 3(𝑛 βˆ’ 1) + 2 |𝑀(𝑒);𝑒 ∈ 𝐸(𝑃𝑛 βŠ™ πΆπ‘š )| = π‘š + 3𝑛 + 1 If |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑛)}| = 2, then we obtain at least two edges which have the same edge weight, which is a contradiction. Accordingly, the lower bound of the local edge antimagic chromatic number of 𝑃𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ πΆπ‘š) β‰₯ π‘š + 3𝑛 + 2. It concludes that the local edge antimagic chromatic number of 𝑃𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝑃𝑛 βŠ™ πΆπ‘š) = 2 + 3𝑛 + π‘š. ∎ Theorem 2.3. The local edge antimagic chromatic number of 𝐢𝑛 βŠ™ πΆπ‘š for 𝑛,π‘š even and 𝑛,π‘š β‰₯ 4 is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ πΆπ‘š) = 3(𝑛 + 1) + π‘š. Proof. The graph 𝐢𝑛 βŠ™ πΆπ‘š is a connected graph with vertex set 𝑉(𝐢𝑛 βŠ™ πΆπ‘š) = {π‘₯𝑖:1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑗 𝑖:1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛 } and edge set 𝐸(𝐢𝑛 βŠ™ πΆπ‘š) = {π‘₯𝑖π‘₯𝑖+1:1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1} βˆͺ {π‘₯1π‘₯𝑛} βˆͺ {π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 : 1 ≀ 𝑗 ≀ π‘š βˆ’ 1; 1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑖π‘₯𝑗 𝑖: 1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯π‘š 𝑖 π‘₯1 𝑖 ,1 ≀ 𝑖 ≀ 𝑛}. The cardinality of the vertex set is |𝑉(𝐢𝑛 βŠ™ πΆπ‘š)| = 𝑛 + π‘šπ‘› and the cardinality of the edge set is |𝐸(𝐢𝑛 βŠ™ πΆπ‘š)| = 2π‘šπ‘› + 𝑛. We define a function bijection 𝑓:𝑉(𝐢𝑛 βŠ™ πΆπ‘š) β†’ {1,2,3,…,|𝑉𝐢𝑛 βŠ™ πΆπ‘š)|} for the graph 𝐢𝑛 βŠ™ πΆπ‘š to be local edge antimagic labeling as follows. 𝑓(π‘₯𝑖) = { 𝑖 + 1 2 , if 𝑖 is odd 𝑛 βˆ’ 𝑖 βˆ’ 2 2 , if 𝑖 is even 𝑓(π‘₯𝑗 𝑖) = { π‘šπ‘› + 1 + ( 𝑖 βˆ’ 2 2 ) βˆ’ ( 𝑗 βˆ’ 1 2 )𝑛, if 𝑖 and 𝑗 are even 𝑛 + 1 + ( 𝑖 βˆ’ 2 2 ) + ( 𝑗 βˆ’ 1 2 )𝑛, if 𝑖 is even and 𝑗 is odd π‘šπ‘› + 𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) βˆ’ ( 𝑗 βˆ’ 2 2 )𝑛, if 𝑖 is odd and 𝑗 is even 2𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) + 𝑛( 𝑗 βˆ’ 1 2 ), if 𝑖 and 𝑗 are odd 𝑓(π‘₯π‘š 𝑖 ) = { π‘›βŒˆ π‘š 2 βŒ‰ + 𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ), 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ π‘›βŒˆ π‘š 2 βŒ‰ + 1 + ( 𝑖 βˆ’ 2 2 ), 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 It is easy to see that 𝑓 is a local edge antimagic labeling of 𝐢𝑛 βŠ™ πΆπ‘š and the edge weights are as follows: On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 45 𝑀(π‘₯𝑖π‘₯𝑖+1) = { 𝑛 + 1, 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ 𝑛 + 2, 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑀(π‘₯1π‘₯𝑛) = 𝑛 + 2 2 𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) = { π‘šπ‘› + 4𝑛 βˆ’ (𝑖 βˆ’ 1), 𝑖𝑓 𝑖 π‘Žπ‘›π‘‘ 𝑗 π‘Žπ‘Ÿπ‘’ π‘œπ‘‘π‘‘ π‘šπ‘› + 3𝑛 βˆ’ (𝑖 βˆ’ 1), 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘šπ‘› + 2(𝑛 + 1) + (𝑖 βˆ’ 2), 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ π‘šπ‘› + 𝑛 + 2 + (𝑖 βˆ’ 2), 𝑖𝑓 𝑖 π‘Žπ‘›π‘‘ 𝑗 π‘Žπ‘Ÿπ‘’ 𝑒𝑣𝑒𝑛 𝑀(π‘₯π‘š 𝑖 π‘₯1 𝑖) = { π‘›βŒˆ π‘š 2 βŒ‰ + 3𝑛 βˆ’ (𝑖 βˆ’ 1),𝑖𝑓 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ π‘›βŒˆ π‘š 2 βŒ‰ + 𝑛 + 2 + (𝑖 βˆ’ 2), 𝑖𝑓 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑀(π‘₯𝑖π‘₯𝑗 𝑖) = { 2𝑛 + 1 + 𝑛( 𝑗 βˆ’ 1 2 ), 𝑖𝑓 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ π‘šπ‘› + 𝑛 βˆ’ 𝑛( 𝑗 βˆ’ 2 2 ),𝑖𝑓 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑀(π‘₯𝑖π‘₯π‘š 𝑖 ) = { π‘›βŒˆ π‘š 2 βŒ‰+ 𝑛 + 1 βˆ’ ( 𝑖 βˆ’ 1 2 ),𝑖𝑓 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ π‘›βŒˆ π‘š 2 βŒ‰+ 2 + ( 𝑖 βˆ’ 2 2 ),𝑖𝑓 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 Hence, we get that the upper bound of the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ πΆπ‘š) ≀ 3(𝑛 + 1) + π‘š. Furthermore, we prove that lower bound of the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ πΆπ‘š) β‰₯ 3(𝑛 + 1) + π‘š. By contradiction, we assume that π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ πΆπ‘š) < 3(𝑛 + 1) + π‘š . Without lost of generality, we gives that 𝑀(π‘₯𝑖π‘₯𝑖+1) β‰  𝑀(π‘₯1π‘₯𝑛) β‰  𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) β‰  𝑀(π‘₯1 𝑖π‘₯π‘š 𝑖 ) β‰  𝑀(π‘₯𝑖π‘₯𝑗 𝑖). Based on Proposition 1 that π›Ύπ‘™π‘Žπ‘’(𝐢𝑛) = 3 and π›Ύπ‘™π‘Žπ‘’(πΆπ‘š) = 3 then we get |{𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛)}| = 3, |{𝑀(π‘₯𝑖π‘₯𝑗 𝑖)}| = π‘š and |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| = 3(𝑛 βˆ’ 1), |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑛)}| = 2 such that |𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛 βŠ™ πΆπ‘š )| = |{𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛)}| + |{𝑀(π‘₯𝑖π‘₯𝑗 𝑖)}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑛)}| = 3 + π‘š + 3(𝑛 βˆ’ 1) + 2 = π‘š + 3𝑛 + 2 If |{𝑀(𝑒);𝑒 ∈ 𝐸((πΆπ‘š)𝑛)}| = 2, then we obtain at least two edges which have same edge weight, which is a contradiction. Thus, we receive that the lower bound of the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ πΆπ‘š) β‰₯ π‘š + 3𝑛 + 3. It concludes that the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ πΆπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ πΆπ‘š) = 3(𝑛 + 1) + π‘š.∎ On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 46 Theorem 2.4. The local edge antimagic chromatic number of 𝐢𝑛 βŠ™ π‘ƒπ‘š for 𝑛 odd and 𝑛,π‘š β‰₯ 3 isπ›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ π‘ƒπ‘š) = 3 + 2𝑛 + π‘š. Proof. The graph 𝐢𝑛 βŠ™ π‘ƒπ‘š is a connected graph with vertex set 𝑉(𝐢𝑛 βŠ™ π‘ƒπ‘š) = {π‘₯𝑖:1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑗 𝑖:1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛 } and edge set 𝐸(𝐢𝑛 βŠ™ π‘ƒπ‘š) = {π‘₯𝑖π‘₯𝑖+1:1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1} βˆͺ {π‘₯1π‘₯𝑛} βˆͺ {π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 : 1 ≀ 𝑗 ≀ π‘š βˆ’ 1; 1 ≀ 𝑖 ≀ 𝑛} βˆͺ {π‘₯𝑖π‘₯𝑗 𝑖: 1 ≀ 𝑗 ≀ π‘š; 1 ≀ 𝑖 ≀ 𝑛}. The cardinality of the vertex set is |𝑉(𝐢𝑛 βŠ™ π‘ƒπ‘š)| = 𝑛 + π‘šπ‘› and the cardinality of the edge set is |𝐸(𝐢𝑛 βŠ™ π‘ƒπ‘š)| = 2π‘šπ‘› + 𝑛 βˆ’ 1. We define a function bijection 𝑓:𝑉(𝐢𝑛 βŠ™ π‘ƒπ‘š) β†’ {1,2,3,…,|𝑉(𝐢𝑛 βŠ™ π‘ƒπ‘š)|} for the graph 𝐢𝑛 βŠ™ π‘ƒπ‘š to be local edge antimagic labeling as follows. 𝑓(π‘₯𝑖) = { 𝑖 + 1 2 , 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ 𝑛 βˆ’ 𝑖 βˆ’ 2 2 , 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑓(π‘₯𝑗 𝑖) = { 𝑛 + 1 + ( 𝑖 βˆ’ 2 2 ) + ( 𝑗 βˆ’ 2 2 )𝑛, 𝑖𝑓 𝑖 π‘Žπ‘›π‘‘ 𝑗 π‘Žπ‘Ÿπ‘’ 𝑒𝑣𝑒𝑛 2𝑛 + π‘›βŒˆ π‘š 2 βŒ‰ + 1 + ( 𝑖 βˆ’ 2 2 ) βˆ’ 𝑛( 𝑗 βˆ’ 1 2 ), 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ 2𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) + ( 𝑗 βˆ’ 2 2 )𝑛, 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘šπ‘› + 𝑛 βˆ’ ( 𝑖 βˆ’ 1 2 ) βˆ’ 𝑛( 𝑗 βˆ’ 1 2 ), 𝑖𝑓 𝑖 π‘Žπ‘›π‘‘ 𝑗 π‘Žπ‘Ÿπ‘’ π‘œπ‘‘π‘‘ It is easy to see that 𝑓 is a local edge antimagic labeling of 𝑃𝑛 βŠ™ πΆπ‘š and the edge weights are as follows: 𝑀(π‘₯𝑖π‘₯𝑖+1) = { 𝑛 + 1, 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ 𝑛 + 2, 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑀(π‘₯1π‘₯𝑛) = 𝑛 + 2 2 (π‘₯𝑖π‘₯𝑖+1) = { 𝑛 + 1, 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ 𝑛 + 2, 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) = { π‘šπ‘› + 3𝑛 βˆ’ (𝑖 βˆ’ 1),𝑖𝑓 𝑖 π‘Žπ‘›π‘‘ 𝑗 π‘Žπ‘Ÿπ‘’ π‘œπ‘‘π‘‘ π‘šπ‘› + 2𝑛 βˆ’ (𝑖 βˆ’ 1), 𝑖𝑓 𝑖 𝑖𝑠 π‘œπ‘‘π‘‘ π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘šπ‘› + 𝑛 + 𝑖, 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ π‘šπ‘› + 2 + 𝑖, 𝑖𝑓 𝑖 𝑖𝑠 𝑒𝑣𝑒𝑛 π‘Žπ‘›π‘‘ 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 𝑀(π‘₯𝑖π‘₯𝑗 𝑖) = { π‘šπ‘› + 1 + 𝑛( 𝑗 βˆ’ 3 2 ),𝑖𝑓 𝑗 𝑖𝑠 π‘œπ‘‘π‘‘ 2𝑛 + 1 + 𝑛( 𝑗 βˆ’ 2 2 ),𝑖𝑓 𝑗 𝑖𝑠 𝑒𝑣𝑒𝑛 On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 47 Hence, we get that the upper bound of the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ π‘ƒπ‘š) ≀ 3 + 2𝑛 + π‘š. furthermore, we prove that the lower bound of the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ π‘ƒπ‘š) β‰₯ 3 + 2𝑛 + π‘š. By contradiction, we assume that π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ π‘ƒπ‘š) < 3 + 2𝑛 + π‘š . Without lost of generality, we gives that 𝑀(π‘₯𝑖π‘₯𝑖+1) β‰  𝑀(π‘₯𝑗 𝑖π‘₯𝑗+1 𝑖 ) β‰  𝑀(π‘₯1 𝑖π‘₯π‘š 𝑖 ) β‰  𝑀(π‘₯𝑖π‘₯𝑗 𝑖). Based on Proposition 1 that π›Ύπ‘™π‘Žπ‘’(𝐢𝑛) = 3 and π›Ύπ‘™π‘Žπ‘’(π‘ƒπ‘š) = 2 then we get |{𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛)}| = 3, |{𝑀(π‘₯𝑖π‘₯𝑗 𝑖)}| = π‘š and |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| = 2(𝑛 βˆ’ 1), |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑛)}| = 1 such that |𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛 βŠ™ π‘ƒπ‘š )| = |{𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛)}| + |{𝑀(π‘₯𝑖π‘₯𝑗 𝑖)}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑖),1 ≀ 𝑖 ≀ 𝑛 βˆ’ 1}| + |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑛)}| |𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛 βŠ™ π‘ƒπ‘š )| = 3 + π‘š + 2(𝑛 βˆ’ 1) + 1 |𝑀(𝑒);𝑒 ∈ 𝐸(𝐢𝑛 βŠ™ π‘ƒπ‘š )| = π‘š + 2𝑛 + 2 If |{𝑀(𝑒);𝑒 ∈ 𝐸((π‘ƒπ‘š)𝑛)}| = 1, then we obtain at least two edges which have same edge weight, Which is a contradiction. Thus, we receive that the lower bound of the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ π‘ƒπ‘š) β‰₯ π‘š + 2𝑛 + 3. It concludes that the local edge antimagic chromatic number of 𝐢𝑛 βŠ™ π‘ƒπ‘š is π›Ύπ‘™π‘Žπ‘’(𝐢𝑛 βŠ™ π‘ƒπ‘š) = 3 + 2𝑛 + π‘š.∎ CONCLUSIONS In this paper we have given the result on the local edge antimagic chromatic number of corona product of path and cycle, namely path corona cycle, cycle corona path, path corona path, cycle corona cycle. Open Problem 1. What is the upper bound of local edge antimagic coloring of corona product of a connected graph? Open Problem 2. What is the lower bound of local edge antimagic coloring of corona product of a connected graph? ACKNOWLEDGMENT We gratefully acknowledge the support from DIKTI Indonesia trough the β€œPenelitian Dosen Pemula” RISTEKDIKTI 2019 research project. REFERENCES [1] S. Arumugam, K. Premalatha, M. Bača and A. SemaničovΓ‘-Feňovčı́kovΓ‘, "Local antimagic vertex coloring of a graph," Graphs and Combinatorics, vol. 33, pp. 275-285, 2017. [2] R. Alfarisi, "dafik, IH Agustin, and AI kristiana," in Journal of physics: conference series, 2018. [3] M. Dettlaff, J. Raczek and I. G. Yero, "Edge subdivision and edge multisubdivision versus some domination related parameters in generalized corona graphs," Opuscula Mathematica, vol. 36, pp. 575-588, 2016. [4] N. Ramya, "On Coloring of Corona Graphs," Indian Journal of Science and Technology, vol. 7, p. 9, 2014. [5] I. G. Yero, D. Kuziak and A. R. Aguilar, "Coloring, location and domination of corona graphs," Aequationes mathematicae, vol. 86, pp. 1-21, 2013. On the Local Edge Antimagic Coloring of Corona Product of Path and Cycle Siti Aisyah 48 [6] A. I. Kristiana, M. I. Utoyo and Dafik, "The lower bound of the r-dynamic chromatic number of corona product by wheel graphs," in AIP Conference Proceedings, 2018. [7] I. H. Agustin, M. Hasan, R. Alfarisi, A. I. Kristiana, R. M. Prihandini and others, "Local Edge Antimagic Coloring of Comb Product of Graphs," in Journal of Physics: Conference Series, 2018. [8] A. I. Kristiana, M. I. Utoyo and others, "On the r-dynamic chromatic number of the corronation by complete graph," in Journal of Physics: Conference Series, 2018. [9] R. M. Prihandini, "Local Edge Antimagic Coloring of Graphs," 2017.