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Pattern Sequence shows a series of numbers and asks for the next one. It is the classic inductive reasoning item found in almost every aptitude test — you infer a rule from examples and apply it. Nothing is remembered; everything is worked out.
A sequence of numbers is shown.
Work out the rule connecting them.
Enter the next number in the series.
Correct answers load a less obvious rule.
Rules progress from arithmetic to multi-step.
A game is ten questions with four answer choices. Easy uses only constant-difference and constant-ratio series; medium adds alternating steps; hard and insane add square-number and Fibonacci-style series, and show longer runs (up to seven terms) with bigger jumps.
A correct answer scores 10 points plus 3 for every correct answer already in your current streak, so the fourth in a row is worth 19. A wrong answer scores nothing and resets the streak. Your best score is saved in this browser.
Inductive reasoning — inferring a general rule from specific instances. It is the reasoning behind hypothesis formation, and it is exactly what sequence items on aptitude tests are there to measure. More logic games to try next: Circuit Builder and Star Battle.
Completing a number series is a test of inductive reasoning — spotting the rule that generated the examples. In a classic 1963 study, Herbert Simon and Kenneth Kotovsky showed that people solve these puzzles by describing the pattern with a few simple relations, such as 'next', 'same' and 'repeat', and that problems get harder as the description gets longer, not as the numbers get bigger.
Series problems appear in many reasoning tests for that reason. Practising them improves how quickly you try the likely rules — constant difference, constant ratio, alternating steps, squares — which is a real and useful habit, if not a general boost to intelligence.
Check the differences between consecutive terms first. Constant differences mean an arithmetic sequence, and that covers a large share of cases.
If the differences are not constant, check the differences of the differences. Two levels resolves most polynomial sequences.
Check ratios next. A constant ratio is a geometric sequence.
If none of those work, look for two interleaved sequences — alternating terms following separate rules is the commonest trick.
Strictly, any finite sequence can be continued in infinitely many ways. In practice the intended rule is the simplest one that fits, and that is the convention these puzzles use.
Differences, then second differences, then ratios, then interleaving. That order covers the great majority.
Sequence items appear on reasoning tests, but a game score is not an assessment.
Learning the checklist above is most of it. The rules used are a small, learnable set.