38 lines
1.5 KiB
JavaScript
38 lines
1.5 KiB
JavaScript
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const bigInt = require('big-integer');
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class GiugaNumbers {
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static main() {
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// Initialize static lists here to ensure they exist before use
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GiugaNumbers.primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59];
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GiugaNumbers.results = [];
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const primeCounts = [3, 4, 5];
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for (const primeCount of primeCounts) {
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GiugaNumbers.primeFactors = new Array(primeCount).fill(0);
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GiugaNumbers.combinations(primeCount, 0, 0);
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}
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GiugaNumbers.results.sort((a, b) => a.minus(b).toJSNumber());
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console.log("Found Giuga numbers: " + GiugaNumbers.results.map(n => n.toString()).join(", "));
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}
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static checkIfGiugaNumber(aPrimeFactors) {
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const product = aPrimeFactors.reduce((acc, val) => acc.multiply(val), bigInt(1));
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for (const factor of aPrimeFactors) {
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const divisor = factor.multiply(factor);
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const numerator = product.minus(factor);
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if (numerator.mod(divisor).notEquals(0)) {
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return;
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}
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}
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GiugaNumbers.results.push(product);
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}
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static combinations(aPrimeCount, aIndex, aLevel) {
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if (aLevel === aPrimeCount) {
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GiugaNumbers.checkIfGiugaNumber(GiugaNumbers.primeFactors);
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return;
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}
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for (let i = aIndex; i < GiugaNumbers.primes.length; i++) {
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GiugaNumbers.primeFactors[aLevel] = bigInt(GiugaNumbers.primes[i]);
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GiugaNumbers.combinations(aPrimeCount, i + 1, aLevel + 1);
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}
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}
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}
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GiugaNumbers.main();
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