The yellow light is flashing.

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An inverse yield curve is always a red light flashing.

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It is Santa, and he has nine reindeer pulling his sleigh, and there's also a flashing light -- they believe that that light is Rudolph.

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"I think it is just another giant, flashing warning light to bitcoin exchanges: If you're not compliant, there are some serious risks, both at the federal and state levels, " said Patrick Murck, legal counsel for the Bitcoin Foundation, a trade group that promotes bitcoin software and security standards.

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The flashing light that worries economists most of all is the fall in capital investment.

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When the device is turned on, a blue light on the front will start flashing once you've managed to figure out the whole pairing thing.

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The concept is certainly familiar, and functions in much the same way as a QR code, generating flashing light that's invisible to the human eye instead of a cumbersome 2D square.

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