Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 9°C. We apply continuously 77°C heat to the field 7x4
What is the temperature (rounded to whole numbers) in the field 3x1 after 150 iterations according to the Gauss-Seidel iteration

Field in the beginning

9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999

Field after 4 iterations (rounded after 4th iteration)

1233333321
2445556864
3466791420158
356791530503215
35781122511285321
3578111935553617
3578101522282211
35678111416137
2455678974
1223344432

Temperature in field 3x1 after 150 iterations: