The first numbers in the triangular rows are 1, 2, 4, 7, 11,...etc. and are defined by N = (n^2 - n + 2)/2soccerisgreat said:The positive integers are written in a triangular array. In what row is the number 1000? So, if I want the number at the end of the 10th row, I take 10*11/2=55. But how do I find what row a number is in?