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title: "Numbers Held Inexactly on the ZX81 (Part 1)"
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excerpt: "First part of a series examining floating-point representation errors in the ZX81 8K ROM. Focuses on integer powers of 2 and how the ZX81 stores them, with programs to examine raw floating-point bytes and demonstrate inaccuracies at specific powers (13, 26, 27, 31, 52-54, 61, 62, etc.)."
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    title: "Syntax/Syntax ZX80 v3 n3"
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pubdate: "March 1982"
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---

# Numbers Held Inexactly on the ZX81 (Part 1)

First part of a series examining floating-point representation errors in the ZX81 8K ROM. Focuses on integer powers of 2 and how the ZX81 stores them, with programs to examine raw floating-point bytes and demonstrate inaccuracies at specific powers (13, 26, 27, 31, 52-54, 61, 62, etc.).