Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 20°C. We apply continuously 128°C heat to the field 7x5
What is the temperature (rounded to whole numbers) in the field 5x5 after 39 iterations according to the Gauss-Seidel iteration

Field in the beginning

20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020
20202020202020202020

Field after 4 iterations (rounded after 4th iteration)

3566777652
5810111212121185
610131415151718158
6111416172029382915
7121517203055885726
71215182342902169136
7121517233663966229
6101316192739493719
581012141823262111
245679111195

Temperature in field 5x5 after 39 iterations: