Crack the Sequence Machine

A sequence can look like a jumble of letters or numbers. But hidden underneath is a tiny repeating machine... spot its moves, and you can predict what comes next!

First, read from left to right. Compare each symbol with the next one. Draw the change between them. For numbers, that change might be add two, then subtract one. For letters, it might be move forward three places in the alphabet. Now look for a change that REPEATS. If the arrows show plus three, minus one, plus three, minus one, the machine has a two-move cycle. Keep the order fixed. Circle matching moves in the same colour. A common trap is to notice only the latest jump and copy it again. Check ALL the gaps instead. One lucky jump is not a rule; the whole repeating pattern must fit every shown symbol.

Let's work through an example. Complete this sequence: four, seven, six, nine, eight, question mark. Choose the number that comes next. Compare four with seven. The first arrow shows plus three, so four becomes seven. Compare seven with six. The next arrow shows minus one, so seven becomes six. Two different moves are now visible. Test that cycle on the next gaps. Six plus three makes nine. Nine minus one makes eight. Both arrows fit, so the repeating rule really is plus three, then minus one. The last move shown was minus one. Do not copy it. Return to the FIRST move in the cycle. Eight plus three makes eleven... so the missing number is eleven. Place eleven in the box, and check the full trail once more: plus three, minus one, plus three, minus one, plus three. It fits!

Remember: compare every gap, find the repeating move or move-cycle, then continue it in order. Check that your rule explains the WHOLE sequence. You have found the machine - now trust your pattern and finish with confidence! Slow eyes, sharp checks, and the next symbol has nowhere to hide.