Triangular Numbers in actions

  • Aaliyah Walters
  • Mulatu Lemma Professor
Keywords: Triangular numbers, Perfect square, Pascal Triangles, perfect numbers


The triangular numbers are formed by the partial sum of the series 1+2+3+4+5+6+7….+n In other words, triangular numbers are those counting numbers that can be written as = 1+2+3+…+ n. So,

T1= 1

T2= 1+2=3

T3= 1+2+3=6

T4= 1+2+3+4=10

T5= 1+2+3+4+5=15

T6= 1+2+3+4+5+6= 21

T7= 1+2+3+4+5+6+7= 28

T8= 1+2+3+4+5+6+7+8= 36


T10 =1+2+3+4+5+6+7+8+9+10=55

In this paper, we investigate some important properties of triangular numbers. Some important results dealing with the mathematical concept of triangular numbers will be proved. We try our best to give short and readable proofs. Most of the results are supplemented with examples.


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Author Biographies

Aaliyah Walters

Department of Mathematics

Savannah State University


Mulatu Lemma, Professor

Department of Mathematics

College of Science and Technology

Savannah State University USA


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How to Cite
Walters, A., & Lemma, M. (2021). Triangular Numbers in actions. GPH - International Journal of Mathematics, 4(04), 32-44. Retrieved from