This is the example:
On Sheet 3

```
   A   B   C
1  A
2  13
3  190

```

These numbers are generated based on data from different Sheets. How could I create a formula on sheet3 that uses a range based on these numbers.
Something like: c= SUM Sheet1!(A1&A2:A1&A3) to sum the range A13 to A190 that is on sheet 1.
The reason I want to do this is because the number stored in A3 is dynamically generated.
Please, help.
Thanks in advance.