The number in the third line is obtained after the first line+1.
The number 20 13 in the first line is -3 to the power of 20 13.
The number 20 13 in the second line is -3 to the power of 20 12.
The number 20 13 in the third line is the power of -3.
(Note: the third power of 20 13 is negative infinity, and no explanation will be given. )