1.0Étienne Ghyshttps://perso.ens-lyon.fr/ghysghyshttps://perso.ens-lyon.fr/ghys/author/ghys/Math in your sanitary pass - Étienne Ghysrich600338<blockquote class="wp-embedded-content" data-secret="geXyQrxjBj"><a href="https://perso.ens-lyon.fr/ghys/2021/09/15/2200/">Math in your sanitary pass</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://perso.ens-lyon.fr/ghys/2021/09/15/2200/embed/#?secret=geXyQrxjBj" width="600" height="338" title="« Math in your sanitary pass » — Étienne Ghys" data-secret="geXyQrxjBj" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script>
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https://www.lemonde.fr/sciences/article/2021/09/15/des-maths-dans-votre-passe-sanitaire_6094702_1650684.html QR codes are loaded with math. The health pass consists of 7,225 little white or black squares, arranged in 85 rows and 85 columns, that encode vaccination status, or test result, or certificate of recovery. This poses some very interesting mathematical and computer problems. The first problem is geometric. The optical reader that scans … Continuer la lecture de →