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Calculators/Maths/Continued fraction expansion
Maths

Continued fraction expansion calculator

Expands a fraction p/q into continued-fraction terms and lists its convergents.

What this calculator does

Continued fraction expansion works out expands a fraction p/q into continued-fraction terms and lists its convergents. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.

The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.

The formula

Formulaa₀=⌊p/q⌋, then repeat on the reciprocal of the remainder; convergents hₙ=aₙhₙ₋₁+hₙ₋₂, kₙ=aₙkₙ₋₁+kₙ₋₂

The inputs explained

FieldWhat to enter
Numerator pA number. Starts at 415.
Denominator qA number. Starts at 93.

Worked examples

Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.

How the answer changes with numerator p

Every other input is held at the calculator’s starting values while numerator p varies. Select any row to load that scenario into the calculator.

How the answer changes with numerator p
Numerator pContinued fractionTermsFinal convergent
208[2; 4; 4; 2; 2]5208/93
311[3; 2; 1; 9; 1; 2]6311/93
415[4; 2; 6; 7]4415/93
623[6; 1; 2; 3; 9]5623/93
830[8; 1; 12; 3; 2]5830/93
1,245[13; 2; 1; 1; 2; 2]6415/31