The second image is an arithmetic sequence.
An arithmetic sequence is defined when there is a common difference among each term.
For the first image, the differences are:
3 - (-1) = 4
-3 - 3 = -6
-1 - (-3) = 2
Since there is no common difference, we don't call this an arithmetic sequence.
For the second image, the differences are:
-2 - 2 = -4
-6 - (-2) = -4
-10 - (-6) = -4
Since they all have a common difference of -4, then we say that the second image is an arithmetic sequence.
Repeat for the others, and you'll find only the second image is an arithmetic sequence.
