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"path": "/article/why-friday-the-13th-is-a-mathematical-inevitability/",
"publishedAt": "2026-03-13T11:00:00.000Z",
"site": "https://www.scientificamerican.com",
"textContent": "No bad luck hereājust lots of fascinating math that explains why the 13th of a month so often falls on a Friday",
"title": "Why Friday the 13th is a mathematical inevitability"
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