等差数列
等差数列；输入、输出与参数范围在实施前细化。
使用步骤
如何使用
- Enter the first term and common difference.
- Choose how many terms to include, up to 100.
- Calculate to see the last term, sum, and generated sequence.
Arithmetic sequence formulas
The nth term is aₙ = a₁ + (n − 1)d, where a₁ is the first term, d is the common difference, and n is the term position. The sum of n terms is Sₙ = n(a₁ + aₙ) ÷ 2.
Finite output by design
This calculator accepts a term count from 1 through 100 and displays the complete finite sequence. Decimal and negative values are supported, while non-finite values and results outside JavaScript’s safe numeric range are rejected.
Private browser calculation
Validation and calculations happen locally in your browser. No values are uploaded or stored by this page.
常见问题
你可能还想知道
What is an arithmetic sequence?
It is a sequence in which the difference between consecutive terms is constant.
Can the common difference be negative or zero?
Yes. A negative difference makes a decreasing sequence, and zero produces a constant sequence.
How many terms can I generate?
Enter from 1 through 100 terms so the full output remains easy to inspect and copy.
Are fractions supported?
Yes. Enter decimal values such as 0.5 or -2.25. The result is shown with a concise decimal format.