Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Game | Date | Team | Score | High points | High rebounds | High assists | Location Attendance | Series |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1.0 | May 2 | @ Chicago | W 103–95 (OT) | Joe Johnson (34) | Al Horford (13) | Jeff Teague (5) | United Center 22,890 | 1–0 |
| 2.0 | May 4 | @ Chicago | L 73–86 (OT) | Jeff Teague (21) | Al Horford (14) | Al Horford (6) | United Center 22,872 | 1–1 |
| 3.0 | May 6 | Chicago | L 82–99 (OT) | Jeff Teague (21) | Josh Smith (13) | Josh Smith (4) | Philips Arena 19,521 | 1–2 |
| 4.0 | May 8 | Chicago | W 100–88 (OT) | Joe Johnson (24) | Josh Smith (16) | Josh Smith (8) | Philips Arena 19,263 | 2–2 |
| 5.0 | May 10 | @ Chicago | L 83–95 (OT) | Jeff Teague (21) | Al Horford (10) | Jeff Teague (7) | United Center 22,980 | 2–3 |
Question:
What is the series number when al horford (10) had the high rebounds?
Answer:
2–3