PHP if is a multiple of an integer

Question

Within a for loop, i need to add some HTML that outputs only when the loop is on a [(multiple of 3) minus 1].

For example, what i could do is:

for($i=0;          


        

Answer 1

the most elegent method is thus

if ($i % 3 === 2) {
  //do stuff
}

as it doesn't add things to the $i value, but all answers are essentially correct!