Series Sense

What comes next? Crack the rule behind each number series

• Single player
• puzzle
• numbers
• iq

Prefer it full screen? Open Series Sense on its own.

About Series Sense

A row of numbers follows a hidden rule. It might add the same amount each time, double, use square numbers, add the two numbers before it, switch between two operations, or weave two series together. Type the next number. When you get it, the gaps between the numbers build out underneath so you can see exactly how the rule works.

What is different about this version

You type the answer instead of choosing from options, so there is no guessing. Every series is checked when it is made so that only one simple rule fits the numbers shown.

How to play Series Sense

1. Look at the gaps between neighbouring numbers first.
2. If the gaps change, look at the gaps between the gaps.
3. Type your answer on the keypad and press Enter.
4. Stuck? Tap Gaps to see the first row of differences for half points.
5. You have three lives. Clear ten levels to master the series.

Controls

Desktop	Type with the number keys, Backspace to delete, minus for negatives and Enter to answer. Escape pauses.
Phone or tablet	Use the on-screen keypad and tap Enter.
Players	One player. Any other characters on screen are run by the game.

Strategy

Start with differences. Steady gaps mean adding; gaps that grow steadily mean the second row is constant; numbers that jump fast usually mean multiplying. If odd and even places look unrelated, read them as two separate series.

Mistakes that cost you the game

• Checking only the last two numbers instead of the whole row.
• Missing that the series alternates between two operations.

Tips

• Square, cube and prime numbers turn up often in later levels.
• A streak multiplies your points, up to three times.

Questions about Series Sense

Is there a time limit?

No. A quiet clock records how long the run took, but no single question is timed.

Does it cost anything?

No. Series Sense is free to play, runs in your browser, and needs no download, install or account.

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