New Delhi, Sept. 5 -- Brain teasers are a fun way to test one's thinking skills. These puzzles give the brain a quick workout. A recent challenge that went viral online has math lovers excited. The puzzle asks users to guess the next number in a series. At first glance, the challenge may look confusing. The answer lies in spotting a hidden number pattern.

The puzzle reads: [1] [4] [9] [16] [25] [?]

Players have five seconds to guess the next number in the sequence. The answer will be easy to figure out for math lovers. Such challenges often appear in competitive exams and other tests as well. Solving them quickly can give you an edge when it comes to examinations.

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