A math puzzle that looks deceptively simple is spreading across social media, challenging users to figure out the next number in a sequence. The numbers given are 2, 5, 11, 23, 47, followed by a question mark.
At first glance, the numbers appear to follow no clear order. The gap between each pair keeps changing, so simply adding the same number each time will not work.
With puzzles like this, the key is not to rush but to look for the common rule behind how each number is produced. Sometimes the pattern is hidden not in the numbers themselves but in the operation performed on the previous value.
Why these puzzles matter
Puzzles of this kind are a good way to train logical thinking, attention and the ability to spot patterns. Solving them usually does not require complex formulas, just testing a few simple possibilities.
Solvers are encouraged to look closely at the jump from 2 to 5, then from 5 to 11, and then from 11 to 23, and to try to work out what single operation could be repeated each time to reach the next number.
Anyone still stuck is advised to first try multiplying each number by the same value, then check whether something needs to be added to the result.
The correct answer
The rule is that each number is multiplied by 2 and then has 1 added to it. That gives:
- 2 x 2 + 1 = 5
- 5 x 2 + 1 = 11
- 11 x 2 + 1 = 23
- 23 x 2 + 1 = 47
Applying the same rule to the last number gives 47 x 2 + 1 = 95.
So the correct answer is 95.
A separate matchstick puzzle also circulating online challenges readers to spot the mistake in just 6 seconds.
