36 lines
717 B
PHP
36 lines
717 B
PHP
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#!/usr/bin/php
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<?php
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define("MAX", 5*(10**7));
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$nextPrime = 2;
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$primes = array($nextPrime);
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while ($nextPrime < sqrt(MAX)) {
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$nextPrime = gmp_intval(gmp_nextprime($nextPrime));
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$primes[] = $nextPrime;
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}
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$sums = array();
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foreach($primes as $outer) {
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$fourth = $outer ** 4;
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if ($fourth >= MAX) {
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break;
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}
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foreach($primes as $middle) {
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$cube = $fourth + $middle ** 3;
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if ($cube >= MAX) {
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break;
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}
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foreach($primes as $inner) {
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$sum = $cube + $inner ** 2;
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if ($sum >= MAX) {
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break;
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}
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$sums[] = $sum;
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}
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}
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}
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echo "Found ".count(array_unique($sums))." numbers\n";
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