Number Sequence Solver
Type a few terms and let the solver spot the pattern and continue it.
Arithmetic sequence
14, 17, 20
Each term goes up by 3. Those are the next three terms.
The gap between neighbouring terms is a constant 3, which is the signature of an arithmetic sequence — you add the same amount every step.
How it works
Give the solver at least three terms and it looks for the two most common patterns. First it checks the differences between neighbours: if they're all the same, the sequence is arithmetic.
If the differences vary, it tries the ratios instead. When each term divided by the one before it lands on the same number, the sequence is geometric, growing by a constant multiplier.
Once it recognises the pattern it uses it to predict the next three terms. If neither the differences nor the ratios stay constant, it tells you plainly that this isn't a simple arithmetic or geometric sequence.
Frequently asked questions
How many terms do I need to enter?
At least three, so there's enough to compare. Two terms could fit endless patterns, but three lets the solver check whether the step or the ratio actually holds steady.
What if my sequence is neither arithmetic nor geometric?
The solver focuses on those two classic patterns, so a sequence like the squares 1, 4, 9, 16 or the Fibonacci numbers won't match. In that case it says so rather than guessing.
Can it handle decimals or a sequence that decreases?
Both are covered. A constant negative difference is still arithmetic, and a ratio below one is still geometric — so 100, 50, 25 is recognised as halving each step.