2.Find the next number in the sequence: 1,−1,3,−5,11,−23,...

The next few numbers should be -89,171,-347,683

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.