120 days is the correct answer!
4 (0 days)
12 (10 days)
36 (20 days)
108 (30 days)
324 (40 days)
972 (50 days)
2,916 (60 days)
8,748 (70 days)
26,244 (80 days)
78,732 (90 days)
236,196 (100 days)
708,588 (110 days)
2,125,764 (120 days)
Please let me know if I am wrong.