One column number 1, - 3,5, - 7,9,11, - 13 What is the 100th number in the tree? Better have a process! thank you

One column number 1, - 3,5, - 7,9,11, - 13 What is the 100th number in the tree? Better have a process! thank you

-199, 2N-1, find the connection, even number is negative, substitute n = 100