<?php

error_reporting(-1);
mb_internal_encoding('utf-8');

$total = 30;
$skip = 5;
$left = 30;
$totalArray = range(1, $total);

while ($left >= $skip) {
	for ($i = 1; $i <= count($totalArray); $i++) {
		if ($i % $skip == 0) {
			unset($totalArray[$i]);
			// $totalArray = array_values($totalArray);
			$left -= 1;
		}
	}
	$total = count($totalArray);
}

echo "Winners: ".implode(", ", $totalArray);