SQLite 3.27

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CREATE TABLE tablename(id INTEGER PRIMARY KEY AUTOINCREMENT, grp INTEGER, value INTEGER);
✓
INSERT INTO tablename(grp, value) VALUES
  (1, 10), (1, 100), (1, 20), (1, 5), (1, 70), 
  (2, 100), (2, 20), (2, 5), (2,35 ), (2, 3), (2, 15), 
  (3, 5), (3, 35), (3, 15), 
  (4, 7), (4, 70), (4, 10), (4, 11), (4, 12), (4, 13), (4, 14), 
  (5, 8), (5, 18), (5, 28), (5, 38);
✓
WITH cte AS (
  SELECT *, 
          value || ' ' ||
          LEAD(value, 1) OVER (PARTITION BY grp ORDER BY id) || ' ' || 
          LEAD(value, 2) OVER (PARTITION BY grp ORDER BY id) str
  FROM tablename
)
SELECT grp, MAX(' ' || '6 100 20 5 12 19' || ' ' LIKE '% ' || str || ' %') flag
FROM cte 
GROUP BY grp;


grp
flag


1
1

2
1

3
0

4
0

5
0


WITH cte AS (
  SELECT *, 
         CASE WHEN ROW_NUMBER() OVER (PARTITION BY grp ORDER BY id) > 2
           THEN GROUP_CONCAT(value, ' ') OVER (
                    PARTITION BY grp ORDER BY id 
                    ROWS BETWEEN 2 PRECEDING AND CURRENT ROW
                )
         END str
  FROM tablename
)
SELECT grp, MAX(' ' || '6 100 20 5 12 19' || ' ' LIKE '% ' || str || ' %') flag
FROM cte 
GROUP BY grp;


grp
flag


1
1

2
1

3
0

4
0

5
0