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I have no real biblical answer for that, but it sounds to me like a) you saw one set of repetitive numbers, which primed you to see others, and b) you enjoy "playing with numbers" (which could be a God-given thing) enough to keep noticing others! It might be the same phenomenon I get when anybody in my family gets a different car-- I never saw a Toyota Sienna on the road until I bought one...now they are All Over The Place. Also, since I *really* enjoy playing with numbers, I notice any interesting combination of them anywhere. Gotta love those grocery bills that go $70.07!