M-Gonal number ±3 = A Perfect square
M. A. Gopalan, V.San geetha · International Journal of Mathematics Trends and Technology · 2015
We search for the ranks of Triangular, Pentagonal, Heptagonal, Nanogonal and Tridecagonal numbers such that each of these M-gonal number -2= a perfect square and the ranks of Pentagonal and Heptagonal such that each of these M-gonal number + 2= a perfect square.