Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 18°C. We apply continuously 71°C heat to the field 2x8
What is the temperature (rounded to whole numbers) in the field 7x1 after 129 iterations according to the Gauss-Seidel iteration

Field in the beginning

18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18

Field after 4 iterations (rounded after 4th iteration)

3	4	5	6	6	6	6	5	4	2
4	7	9	10	10	11	10	9	7	4
5	9	11	13	13	14	13	12	9	5
6	10	13	14	15	15	15	14	10	5
6	10	14	15	16	17	16	15	11	6
6	12	17	18	18	18	17	15	11	6
8	17	26	25	22	20	18	15	11	6
12	30	52	38	27	21	17	14	10	5
16	46	118	53	29	19	14	11	7	4
10	24	42	28	17	11	8	6	4	2

Temperature in field 7x1 after 129 iterations:

18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18

3	4	5	6	6	6	6	5	4	2
4	7	9	10	10	11	10	9	7	4
5	9	11	13	13	14	13	12	9	5
6	10	13	14	15	15	15	14	10	5
6	10	14	15	16	17	16	15	11	6
6	12	17	18	18	18	17	15	11	6
8	17	26	25	22	20	18	15	11	6
12	30	52	38	27	21	17	14	10	5
16	46	118	53	29	19	14	11	7	4
10	24	42	28	17	11	8	6	4	2

18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18

3	4	5	6	6	6	6	5	4	2
4	7	9	10	10	11	10	9	7	4
5	9	11	13	13	14	13	12	9	5
6	10	13	14	15	15	15	14	10	5
6	10	14	15	16	17	16	15	11	6
6	12	17	18	18	18	17	15	11	6
8	17	26	25	22	20	18	15	11	6
12	30	52	38	27	21	17	14	10	5
16	46	118	53	29	19	14	11	7	4
10	24	42	28	17	11	8	6	4	2

18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18
18	18	18	18	18	18	18	18	18	18

3	4	5	6	6	6	6	5	4	2
4	7	9	10	10	11	10	9	7	4
5	9	11	13	13	14	13	12	9	5
6	10	13	14	15	15	15	14	10	5
6	10	14	15	16	17	16	15	11	6
6	12	17	18	18	18	17	15	11	6
8	17	26	25	22	20	18	15	11	6
12	30	52	38	27	21	17	14	10	5
16	46	118	53	29	19	14	11	7	4
10	24	42	28	17	11	8	6	4	2