How to make an incremented value in SCSS?

Question

css

Is it possible to use SASS to gradually increase indentation? Those. each next value should be 5px to the left. Unfortunately, nothing smarter than in the example came to mind, but that's not it.
Here is the code:

@mixin last-childs {
    @for $i from 2 through 7 {
        &:nth-last-child(#{$i}) {
           margin-left: calc(40px - #{$i}px);
        }
    }
}

Or do you have to manually write?
It should be like this:

&:nth-last-child(7) {
        margin-left: 10px;
    }
    &:nth-last-child(6) {
        margin-left: 15px;
    }
    &:nth-last-child(5) {
        margin-left: 20px;
    }
    &:nth-last-child(4) {
        margin-left: 25px;
    }
    &:nth-last-child(3) {
        margin-left: 30px;
    }
    &:nth-last-child(2) {
        margin-left: 35px;
    }
    &:last-child {
        margin-left: 40px;
    }

Answer 1

In fact, your example is almost correct, just modify a little:

@mixin last-childs {
    @for $i from 7 through 1 {
        &:nth-last-child(#{$i}) {
           margin-left: 40px - 5px * ($i - 1);
        }
    }
}