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# Wouldn't you want to use 4+3n? The line with elements 13, 14 and 15 won't get the clear.

When you use 4n, the 2nd, 3rd and 4th row will all be effected, but the 5th row contains elements 13, 14, and 15 none of which are a multiple of 4. If we were to have this problem with a lot of elements, would the spacing on that row, and any other row that doesn't contain an element with index that is a multiple of 4, be incorrectly formatted?

"n" basically stands for 0, 1, 2, 3, 4, 5, 6, and so on.

So if we have "4n", we are affecting elements:

• 4x0 = nothing
• 4x1 = 4th element
• 4x2 = 8th element
• 4x3 = 12th element
• 4x4 = 16th element

If we use "4+3n", we affect:

• 4+(3x0) = 4th element
• 4+(3x1) = 7th element
• 4+(3x2) = 10th element
• 4+(3x3) = 13th element
• 4+(3x4) = 16th element

I understand that... My claim is that in the example you want to affect the 4th, 7th, 10th, etc elements because there are three columns.

Nevermind, it is answered in the code correction under the video.