space scales: what is 8px / powers-of-two

[bchenSyd]

the document says

The default scale is based on an 8px/powers-of-two grid: [ 0, 4, 8, 16, 32, 64, 128, 256, 512 ], which helps keep spacing consistent and elements aligned even when nesting components.

so far I have noticed m={1} is 8px , m={2} is 16px m ={3} is 32px; m={1/2} is 0.5px

where does 4 fit in this pattern??

[bchenSyd]

isn't powers of two grid be [0,2,4,8,16,32 .... ]

I don't understand the logic behind the gird mentioned in the document

[jxnblk]

Some people refer to it as an "8px grid" – but it's essentially based on powers of two