According to Wittgenstein's Finite Rule Paradox every finite sequence of numbers can be a described in infinitely many ways and so can be continued any of these ways - some simple, some complicated but all equally valid. Conversely, it is possible to find a rule such that any number of your choice can be the next one.
Using the simplest polynomial of order 6, the answer is -628.
If your pattern is plus 1, minus 2, times 3, divide by 4, then the last number should be 5 and the next number should be 15.
24
90 because 66+24 = 90
291
24
651 is the next number.
25-1=24 24-2=22 22-3=19 19-4=15 15-5=10 The next number in the series is 10.
10
24
24
90 because 66+24 = 90
24
291
24
24
24
8
61