1. Avem sirul 1, 2, 3, 4, ?, 6. Ce numar lipseste?

2. Avem sirul 64, 32, 16, 8, ?, 2. Ce numar lipseste?

3. Avem sirul 1, 2, 4, 7, ?, 16. Ce numar lipseste?

4. Avem sirul 1, 10, 11, 20, ?, 30. Ce numar lipseste?

5. Avem sirul 1, 5, 32, 288, ?, 50069. Ce numar lipseste?

6. Avem sirul 1, 5, 14, 30, ?, 91. Ce numar lipseste?

7. Avem sirul 1, 6, 4, 9, ?, 12. Ce numar lipseste?

8. Avem sirul 128, 64, 32, 16, ?, 4. Ce numar lipseste?

9. Avem sirul 1, 1, 2, 4, ?, 16. Ce numar lipseste?

10. Avem sirul 3, 10, 6, 13, ?, 16. Ce numar lipseste?