Not that these variations follow a pure sine wave but they have been cyclical.

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Its movement looks like a regular sine wave function within pretty defined parameters, and this pattern has held true for the last 1200 days.

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Cantering loosely down sand-covered roads sighting down a sine-wave of bonnet, lazy, dusty oppositelock applied at speeds rarely above a brisk trotting pace and the smell: scorched dirt, cooking tarmac, a whiff of hot oil, burning chrome and heat.

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In a solar system, each planet has its own sine wave.

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