Why Does It Say Undetermined?

A finite list can fit infinitely many rules. The tool reports only its supported transparent families instead of guessing.

Number Sequence Calculator

Detect transparent arithmetic, geometric or previous-two-term patterns and project up to twenty additional terms.

Pattern Desk

Known Terms

Inspect arithmetic, geometric and previous-two-term sequences without inventing a rule when evidence is insufficient.

SequenceTerms To Project

Many finite lists support multiple possible rules. This tool reports only three transparent families and labels anything else undetermined.

Sequence Tape

Arithmetic · Common Difference 3

Projected terms are visually separated from the observations you supplied.

2581114→1720232629

First Differences

3 · 3 · 3 · 3

Adjacent Ratios

2.5 · 1.6 · 1.375 · 1.27273

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What Is the Number Sequence Calculator?

The Number Sequence Calculator checks a supplied list against arithmetic, geometric and previous-two-term patterns. It exposes first differences and adjacent ratios and refuses to invent a rule when the finite evidence does not match a supported family.

How It Works

Paste at least two comma- or space-separated numbers and choose how many terms to project. Compare the detected rule with the difference and ratio ledgers.

When to Use It

Use it for classroom sequence work, QA of generated series and quick checks of simple progressions.

Frequently Asked Questions

Why Does It Say Undetermined?: A finite list can fit infinitely many rules. The tool reports only its supported transparent families instead of guessing.

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