What is the next number?
2, 9, 28, 65, ____
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 126
Each term is one more than a perfect cube: \(n^3+1\) for \(n=1,2,3,4,\ldots\)
\(1^3+1=2\), \(2^3+1=9\), \(3^3+1=28\), \(4^3+1=65\)
Next: \(5^3+1=125+1=126\)