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<?php // The magic three sequence is the sum of the previous three values minus 1. // // 0,1,1,1,2,3,5,9,16, function magicThree($n) { if ($n < 1) return; $n--; // To an index; $s = array(0,1,1,1); if ($n > 3) { for ($i = 4; $i <= $n; $i++) { $s[$i] = $s[$i-1] + $s[$i-2] + $s[$i-3] - 1; } } print $s[$n]; } magicThree(7); ?>
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.33, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
5

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301.28 ms | 405 KiB | 421 Q