A column number 1, negative 3,5, negative 7,9, negative 11,13, then what is the 100th number in the column number?

A column number 1, negative 3,5, negative 7,9, negative 11,13, then what is the 100th number in the column number?

-199
2 + (3 - 2) = 3, is the second number (even number), plus a minus sign
3 + (4 - 3) = 5, is the third (singular), without sign
.
It is concluded that N + (n + 1-N) (n stands for the number)
The 100th number: 100 + (100 + 1 - 100) = 199 (even number), plus minus sign
=-199