Isosceles Triangular Numbers

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Somphong Jitman
Kampon Awachai Awachai
Phutthichai tanla Tanla


Triangular numbers have been of interest and extensively studied. In this work, we focus on an isosceles triangular number which is a generalization of a triangular number. Properties of isosceles triangular numbers have been determined together with a necessary condition for a positive integer to be isosceles triangular. Characterizations of odd and even isosceles triangular numbers have been also provided. Finally, links between isosceles triangular numbers and regular polygonal numbers has been given as well.

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How to Cite
Jitman, S., Awachai, K. A., & Tanla, P. tanla. (2018). Isosceles Triangular Numbers. Mathematical Journal by The Mathematical Association of Thailand Under The Patronage of His Majesty The King, 62(692), 39–49. Retrieved from
Research Article


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