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Note G

Ada Lovelace · 1843

Ada Lovelace's final note to her translation of Menabrea's article, containing a step-by-step table for computing Bernoulli numbers on Babbage's Analytical Engine.

Note G is Lovelace's own algorithm, the achievement for which she is remembered as a pioneer of computing.

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Scanned page titled 'Diagram for the computation by the Engine of the Numbers of Bernoulli. See Note G (page 722 et seq.)'. It is a dense table with columns for operation number, nature of operation, variables acted upon and receiving results, data and working variables, and results, filled with rows of symbols, formulas and numbers.
Ada Lovelace, Note G, diagram of an algorithm for the Analytical Engine, 1843.

About this source

What it is

Note G is the last of seven notes Ada Lovelace added to her 1843 English translation of an article by Luigi Menabrea about Charles Babbage's Analytical Engine. It contains a detailed table of operations showing how the machine could calculate Bernoulli numbers.

Why it matters

Although the Analytical Engine was never built, this note is often called the first published algorithm written for a computer. It shows Lovelace going beyond simply explaining Babbage's machine, working out the mathematics herself and even correcting an error Babbage had made. The note also reveals her bigger idea: that such a machine could one day process more than numbers.

Look closer

  • Why do you think Lovelace organised her calculation as a table rather than plain text?
  • What does it tell you about her role that Babbage later admitted she found his mistake?
  • What does the note leave out, since the machine it describes was never actually built?

This document is part of the curated material that grounds the AI version of Ada Lovelace on Humy.ai — when students ask about related events, the AI can quote it and cite it.

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