Which of these sequences is NOT an arithmetic sequence?
2,4,6,82, 4, 6, 82,4,6,8
10,7,4,110, 7, 4, 110,7,4,1
1,2,4,81, 2, 4, 81,2,4,8
5,5,5,55, 5, 5, 55,5,5,5