The general formula as you asked is:
Using fixed values for today "02/10/2019" for dates the above formula would be:
We use eomonth(today(),-1), so we take as our starting date the last day of the previous month.
We multiply the whole formula by -1 because we ...
Solution with a Formula :
A1 : =ArrayFormula(if(
text((round(ROW(A1:A100)/4)*7)+43730,"dddd dd mmm yy")
Solution with drag and drop
Enter the dates in the cells : A1 is the first sunday,
A5 is the second with this formula =A1+7
It looks like you are looking for a single formula solution but they could be hard to understand and maintain, specially if you aren't familiar on how the Google Sheets related features works.
Dates. Google Sheets handles dates as serialized numbers, where a day is one unit.
Because of the above feature we could create a list of dates by ...