Math & AlgebraGenerated accuracy model review: 2026-05-06

Number Sequence accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

Formulas used: **Arithmetic:** * Nth Term (aₙ) = a₁ + (n-1)d * Sum (Sₙ) = (n/2) × (2a₁ + (n-1)d) **Geometric:** * Nth Term (aₙ) = a₁ × r^(n-1) * Sum (Sₙ) = a₁ × (1 - r^n) / (1 - r)

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

Type: Arithmetic (+)
First Term (a1): 1
Common Diff/Ratio (d/r): 2
Term Number (n): 10

Expected outputs

Nth Term (an): 19
Sum (Sn): 100

Known limitations

This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
Use the result as a planning estimate unless the calculator page states a stricter purpose.

Assumptions

The term number n should be a positive whole number.
Arithmetic mode uses an additive difference; geometric mode uses a multiplier.
The calculator returns the finite sum for the first n terms, not an infinite-series result.

Unit handling

Type accepts one of the configured options.
First Term (a1) accepts numeric values.
Common Diff/Ratio (d/r) accepts numeric values.
Term Number (n) accepts numeric values.

Rounding rules

Number displays use up to 2 decimal places in the calculator UI.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current number-sequence-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Number Sequence.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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