Mathematics · Precalculus

Arithmetic Sequence Calculator

Find the nth term of a sequence with a constant difference.

Runs locally
Your numbers

Inputs and results stay in this browser. Change one value at a time to explore the relationship.

Your inputCalculatedPassed forward in chains
nth term32
Number of jumps9

Calculation steps

  1. From term 1 to term 10 there are 9 jumps.
  2. Change = 9 × 3 = 27.
  3. a_10 = 5 + 27 = 32.

Understand Arithmetic sequence

One idea, three depths

Choose how deeply to explain Arithmetic sequence

Arithmetic sequence: Find the nth term of a sequence with a constant difference.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using Arithmetic sequence to answer this question: find the nth term of a sequence with a constant difference? Enter First term, Common difference, Term number n; the calculator shows nth term. For example: With first term 5 and difference 3, term 10 is 5+9×3=32. The answer tells you nth term.

Age 15Explain it to a 15-year-oldConnect it to the formula

There are n−1 equal jumps from the first term to the nth term, each adding the common difference d. The rule is aₙ = a₁ + (n−1)d. Its input values are First term, Common difference, Term number n, and the main result is nth term. For example: With first term 5 and difference 3, term 10 is 5+9×3=32.

CollegeExplain it at college levelState the model precisely

This calculator evaluates the stated arithmetic sequence relation over the valid mixed integer and real-number domain stated below. The implemented relation is aₙ = a₁ + (n−1)d, evaluated from First term, Common difference, Term number n to produce nth term. There are n−1 equal jumps from the first term to the nth term, each adding the common difference d. Use n−1 differences because the first term occurs before any jump.

Inputs and valid domain

  • First term must be a finite real number.
  • Common difference must be a finite real number.
  • Term number n must be an integer, at least 1.

Important boundary: Use n−1 differences because the first term occurs before any jump.

The formula

aₙ = a₁ + (n−1)d

How the calculator works through it

It substitutes First term, Common difference, Term number n into the formula and exposes every numerical step above. The main output is nth term, accompanied by Number of jumps.

Read the result correctly

The nth term is the direct answer to “find the nth term of a sequence with a constant difference.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.

A worked check

With first term 5 and difference 3, term 10 is 5+9×3=32.

Where this model stops being reliable

Use n−1 differences because the first term occurs before any jump.

Learn it by changing one value

Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.

Dictionary terms behind this calculator

Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.

These foundations help you understand why Arithmetic sequence works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.

Hard requirements

  • Reading formulas and substituting values

    Arithmetic sequence uses aₙ = a₁ + (n−1)d. You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.

    Review this foundation about 4 min

Strong support

Optional enrichment

Learn the missing foundationsI already know these — show the code

Mathematics → algorithm → program

Implement this calculation in code

These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.

Algorithm

  1. Read First term, Common difference, Term number n.
  2. Evaluate the principal relationship: aₙ = a₁ + (n−1)d.
  3. Return nth term and check the domain conditions described above.
Python
            from math import *

def arithmetic_sequence(a, b, n) -> float:
    return (a + ((n - 1.0) * b))

assert abs(arithmetic_sequence(5, 3, 10) - 32) < 1e-6 * max(1.0, abs(32))
          
Current calculator valuesUpdates when you change an input above.
              
            
C
            #include <assert.h>
#include <math.h>

double arithmetic_sequence(double a, double b, double n) {
    return (a + ((n - 1.0) * b));
}

int main(void) {
    const double expected = 32;
    const double actual = arithmetic_sequence(5, 3, 10);
    assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
C++
            #include <cassert>
#include <cmath>
#include <numbers>

double arithmetic_sequence(double a, double b, double n) {
    return (a + ((n - 1.0) * b));
}

int main() {
    constexpr double expected = 32;
    const double actual = arithmetic_sequence(5, 3, 10);
    assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
Linux x86-64 assembly

x86-64 NASM · System V ABI · Linux · SSE2 with libm where required

            ; double arithmetic_sequence(double a, double b, double n)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
global arithmetic_sequence
section .text

arithmetic_sequence:
    push rbp
    mov rbp, rsp
    sub rsp, 64
    movsd [rbp-8], xmm0
    movsd [rbp-16], xmm1
    movsd [rbp-24], xmm2
    mov rax, 0x3ff0000000000000
    movq xmm0, rax
    movsd [rbp-56], xmm0
    movsd xmm0, [rbp-24]
    subsd xmm0, [rbp-56]
    movsd [rbp-48], xmm0
    movsd xmm0, [rbp-48]
    mulsd xmm0, [rbp-16]
    movsd [rbp-40], xmm0
    movsd xmm0, [rbp-8]
    addsd xmm0, [rbp-40]
    movsd [rbp-32], xmm0
    movsd xmm0, [rbp-32]
    leave
    ret
          
Current calculator valuesUpdates when you change an input above.
              
            
MATLAB
            function result = arithmetic_sequence(a, b, n)
    result = (a + ((n - 1.0) * b));
end
          
Current calculator valuesUpdates when you change an input above.
              
            
Wolfram Language
            ClearAll[mwCalculate];
mwCalculate[a_, b_, n_] := (a + ((n - 1.0) * b));
          
Current calculator valuesUpdates when you change an input above.
              
            

Continue in mathematical software

The downloaded file includes your current inputs and first calculated result. It is created locally.

Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.

Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations

Standards, reading and academic references

Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.

Algebra and Trigonometry 2e

Read the related free OpenStax mathematics chapters
Cite this book
APA 7
Abramson, J. (2021). Algebra and trigonometry 2e. OpenStax. https://openstax.org/books/algebra-and-trigonometry-2e/pages/1-introduction-to-prerequisites
MLA 9
Abramson, Jay. Algebra and Trigonometry 2e. OpenStax, 2021, https://openstax.org/books/algebra-and-trigonometry-2e/pages/1-introduction-to-prerequisites.
Chicago author-date
Abramson, Jay. 2021. Algebra and Trigonometry 2e. Houston, TX: OpenStax. https://openstax.org/books/algebra-and-trigonometry-2e/pages/1-introduction-to-prerequisites.

OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

APA 7

MW SysArc. (2026, July 21). Arithmetic Sequence Calculator. MW SysArc Tools. https://math.mwsysarc.com/precalculus/arithmetic-sequence-calculator

MLA 9

MW SysArc. “Arithmetic Sequence Calculator.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/precalculus/arithmetic-sequence-calculator. Accessed 31 Aug. 2026.

Chicago 17

MW SysArc. “Arithmetic Sequence Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/precalculus/arithmetic-sequence-calculator.

Harvard

MW SysArc (2026) ‘Arithmetic Sequence Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/precalculus/arithmetic-sequence-calculator (Accessed: 31 August 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_arithmetic_sequence_2026,
  author = {{MW SysArc}},
  title = {Arithmetic Sequence Calculator},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://math.mwsysarc.com/precalculus/arithmetic-sequence-calculator},
  note = {Published July 21, 2026; accessed August 31, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Arithmetic Sequence Calculator
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-08-31
UR  - https://math.mwsysarc.com/precalculus/arithmetic-sequence-calculator
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Arithmetic sequence do?

Find the nth term of a sequence with a constant difference.

How does the Arithmetic sequence work?

The calculator applies aₙ = a₁ + (n−1)d. There are n−1 equal jumps from the first term to the nth term, each adding the common difference d.

What can I learn from the Arithmetic sequence?

It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.

Last reviewed . Calculations tested .

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