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:
| Round | Clubs remaining | Clubs involved | Winners from previous round | New entries this round | Leagues entering this round |
| --- | --- | --- | --- | --- | --- |
| Preliminary round | 129.0 | 34.0 | none | 34 | Levels 4 and 5 in football league pyramid |
| Second round | 64.0 | 64.0 | 48 | 16 | Gambrinus liga |
| Third round | 32.0 | 32.0 | 32 | none | none |
| Fourth round | 16.0 | 16.0 | 16 | none | none |
| Quarter finals | 8.0 | 8.0 | 8 | none | none |
| Semi finals | 4.0 | 4.0 | 4 | none | none |
Question:
Name the least clubs involved for leagues being none for semi finals
Answer:
4.0