The number rule for this sequence is that each time the number goes up, it does so by whatever the previous amount added was, multiplied by two. So far we can see the sequence is +50, +25-, +500, +1000, so we assume that next it will be +2000 and the next number in the sequence will therefore be 22,000
The sequence 18,250; 18,500; 19,000; 20,000 follows a pattern where each difference doubles, starting from 250. The next term in the sequence is likely 22,000. This is because the differences are 250, 500, and 1,000, which double each time.
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