Yes, the numbers 9, 4, -1, and -6 form a sequence. A sequence is simply an ordered list of numbers. In this case, these four numbers are ordered, so they constitute a sequence.
However, if you're asking whether this sequence follows a specific pattern or rule, we can analyze the differences between consecutive terms:
- The difference between 9 and 4 is -5.
- The difference between 4 and -1 is -5.
- The difference between -1 and -6 is -5.
Since each term decreases by 5 from the previous term, this sequence can be described as an arithmetic sequence with a common difference of -5.