Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 15°C. We apply continuously 143°C heat to the field 3x8
What is the temperature (rounded to whole numbers) in the field 9x7 after 57 iterations according to the Gauss-Seidel iteration

Field in the beginning

15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515
15151515151515151515

Field after 4 iterations (rounded after 4th iteration)

2445555532
4678999863
479111111111084
5811121313131194
5911131414141295
59141919181613105
512253833262015105
722529162382416105
931862299545241484
6204580502715952

Temperature in field 9x7 after 57 iterations: