Number sequences (11+ style)
11+ sequences include arithmetic, geometric, alternating, and term-by-term Fibonacci-like patterns.
11+ number-sequence questions move beyond ‘add the same number each time’. Look for: alternating differences (e.g. +2, +4, +2, +4), squared sequences (1, 4, 9, 16, ...), or recursive patterns (each term depends on the previous two).
Worked examples
3, 7, 15, 31, 63: each = 2×previous + 1.
2, 5, 11, 23: each = 2×previous + 1.
1, 4, 9, 16, 25 — square numbers (n²).
Frequently asked questions
Spot the pattern fast?
Always compute the differences first. If they're constant, it's arithmetic. If they double, it's geometric ratio 2.
How many to look for?
Usually 3-5 terms shown; the missing one or two are at the end or middle.