Nestor designed a screen saver for his computer. It starts with 4 dots arranged in a square. After 5 seconds, each dot is replaced by 3 dots arranged in a triangle, giving 12 dots in total. After 5 more seconds, each dot is again replaced by 3 dots arranged in a triangle, giving 36 dots total. If the pattern continues, after how many seconds will there be at least 3,000 dots? Show your work.