Mathematics for IGCSE & O level - Sequences (Section 3 - No. 34)
Which of these sequences has a constant second difference?
1, 3, 6, 10, ...
2, 4, 8, 16, ...
3, 6, 9, 12, ...
1, 4, 9, 16, ...
解释
Sequences with a constant second difference are quadratic.