45 lines
852 B
Markdown
45 lines
852 B
Markdown
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---
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id: 5900f43e1000cf542c50ff4f
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title: 'Problem 209: Circular Logic'
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challengeType: 5
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forumTopicId: 301850
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dashedName: problem-209-circular-logic
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---
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# --description--
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A k-input binary truth table is a map from k input bits
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(binary digits, 0 \[false] or 1 \[true]) to 1 output bit. For example, the 2-input binary truth tables for the logical AND and XOR functions are:
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x y x AND y000010100111x y x XOR y000011101110How many 6-input binary truth tables, τ, satisfy the formula
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τ(a, b, c, d, e, f) AND τ(b, c, d, e, f, a XOR (b AND c)) = 0 for all 6-bit inputs (a, b, c, d, e, f)?
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# --hints--
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`euler209()` should return 15964587728784.
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```js
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assert.strictEqual(euler209(), 15964587728784);
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```
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# --seed--
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## --seed-contents--
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```js
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function euler209() {
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return true;
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}
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euler209();
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```
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# --solutions--
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```js
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// solution required
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```
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