PHP检查值是否是具有共同差异的数字序列的一部分

Question

I'm writing a script that needs to identify every 7th number where the first number of the sequence is 0 (so the sequence is 6, 13, 20, 27, 34, 41, 48, etc.)

Here's what I've got so far (which works in a limited way), but I'd prefer to write a loop so that the values in the sequence don't have to be hardcoded:

<?php

$x = 7;

if ($x === 6 || $x === 13 || $x === 20 || $x === 27 || $x === 34 || $x === 41 || $x === 48) {
    $result = 1;
  } else {
    $result = 0;
}

echo $result;

?>

Thanks in advance for any advice!

---

Update: Here's my updated script using @robbieaverill 's solution and checking the values against an array. There are many great solutions here, thanks everyone!

<?php

$divisor = 7;
$limit = 500; 

$sequence = array();

for ($i = 0; $i <= $limit; $i++) {
  if (is_int(($i + 1) / $divisor)) {
    $sequence[] = $i;
  }
}

$x = 41;

if (in_array($x, $sequence, true)) {
  $result = 1;
} else {
  $result = 0;
}

echo $result;
?>

The output here is 1, indicating that if the value of $x is 41 it is found within the $sequence array.

Answer 1

There's probably a bunch of different ways you could do this. If you need to identify numbers that are evenly divisible by 7 (plus one, because you're zero based), you could do something like this:

$divisor = 7;
$limit = 100; // when do you want to stop searching?

for ($i = 0; $i <= $limit; $i++) {
    if (is_int(($i + 1) / $divisor)) {
        var_dump($i);
    }
}

Note that is_int() is checking whether the divided result is a whole number, it'd return false for a decimal/floating point number.