SQL Server 2019

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create table data (week int, amount decimal(10,2))
insert into data values (1, 100), (2, 100), (3, 100), (4, 100),
(5, 100000), (6, 100), (7, 50000), (8, 50000), (9, 50000), (10, 100)

create table bad_weeks (week int)
insert into bad_weeks values (5), (7), (8), (9)
14 rows affected

SELECT * 
FROM data as d
  OUTER APPLY
  (
	  SELECT SUM(prev_amount) as sum_not_bad
	  FROM
		  (SELECT TOP(4) (p.amount)as prev_amount
		   FROM data as p
			   LEFT JOIN bad_weeks as b
					ON p.week = b.week
		   WHERE p.week < d.week
				AND b.week is null
		   ORDER BY p.week DESC
		  )a
  )oa


week
amount
sum_not_bad


1
100.00
null

2
100.00
100.00

3
100.00
200.00

4
100.00
300.00

5
100000.00
400.00

6
100.00
400.00

7
50000.00
400.00

8
50000.00
400.00

9
50000.00
400.00

10
100.00
400.00


SELECT * 
FROM data as d
  OUTER APPLY
  (
	SELECT SUM(a.prev_amount) as sum_not_bad
	FROM
	(
		SELECT p.amount as prev_amount
			,ROW_NUMBER() OVER(ORDER BY p.week DESC) as rn			
		FROM data as p
			LEFT JOIN bad_weeks as b
				ON p.week = b.week
		WHERE p.week < d.week
			AND b.week is null	
	)as a
	WHERE a.rn<=4
  )oa


week
amount
sum_not_bad


1
100.00
null

2
100.00
100.00

3
100.00
200.00

4
100.00
300.00

5
100000.00
400.00

6
100.00
400.00

7
50000.00
400.00

8
50000.00
400.00

9
50000.00
400.00

10
100.00
400.00

week	amount	sum_not_bad
1	100.00	null
2	100.00	100.00
3	100.00	200.00
4	100.00	300.00
5	100000.00	400.00
6	100.00	400.00
7	50000.00	400.00
8	50000.00	400.00
9	50000.00	400.00
10	100.00	400.00