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self-descriptive number (Definition)
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"self-descriptive number" is owned by PrimeFan. [ full author list (3) | owner history (2) ]
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Other names:  self descriptive number
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Cross-references: hexadecimal, OEIS, sequence, bases, range, iterator, simple, digit, integer, base
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This is version 6 of self-descriptive number, born on 2006-05-02, modified 2008-05-21.
Object id is 7892, canonical name is SelfDescriptiveNumber.
Accessed 1505 times total.

Classification:
AMS MSC11A63 (Number theory :: Elementary number theory :: Radix representation; digital problems)

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how to describe algebraically by Lando47 on 2006-05-03 17:41:43
I'm not entirely sure d_x = \sum_{d_i = x} is correct. I understand what it means (digit y at position x is the total number of instances of digit y in the number) but I'm not sure if the formula is mathematically correct. Can this be fed to a CAS so that it understands what is meant?
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