I only know of people who have saved in the first list
week 1 = $1
and one friend who each month did the following
week 2 = $ 2
week 3 = $4
week 4 = $8
And no, for some people saving $100 a month just doesn't work.
I"ve seen a similar challenge that began with $1 and just added an extra dollar each week. Last week, you're only putting into $52.