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The check digit that catches a mistyped number
engineering
The Luhn and ISBN algorithms embed a check digit so a single wrong digit is caught before it becomes a wrong order or a wrong book. Two standards, both verified. Worked & sealed by the engine — Luhn(4532 0151 1283 0366) is valid · ISBN-13 978-0-306-40615-7 is valid. [HOLDS; open the seal to re-check.]
source
card id
card_works_luhn
address
UNPLACED
adjoining cards
- on the shelf of → The Works — sealed, worked demonstrations — a member of the the-works shelf in the keeping
- paves → The Floor of Discovery — one floor, and by its design the fear of God — A worked, engine-sealed demonstration — a paving-stone of the floor of reality.
- demonstrates → Luhn(4532 0151 1283 0366) is valid · ISBN-13 978-0-306-40615-7 is valid — A worked demonstration in the same field (document_validation).
- adjacent → The 3-4-5 the builders use to square a corner — Neighbouring worked demonstrations in the same part of the volume.
- adjacent → The exposure value of a camera setting — Neighbouring worked demonstrations in the same part of the volume.
- adjacent → A 12-volt circuit: the current it draws, the power it burns — Neighbouring worked demonstrations in the same part of the volume.
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