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What are Shoulders?
Please see this introductory material on shoulders.
Why is there no "/" to mark the end of a shoulder?
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In fact, in-house ARK administrators always know where the shoulder ends, provided it was chosen using the "first-digit convention". A primordinal shoulder is a sequence of one or more 187180621 betanumeric letters ending in a digit. This means that the shoulder is all letters (often just one) after the NAAN up to and including the first digit encountered after the NAAN. Another advantage of primordinal shoulders is that there is an infinite number of them possible under any NAAN.
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