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I'm trying to solve this little problem. So far no luck. Could anyone help? Thanks in advance :)

What is the ten digit number such that the i-th digit is the number of i's in the number ( 0<= i <= 9) (the 0th position is number of zeros in the number, the 1st position is number of ones in the number,…)?

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    6210001000 works.2011-05-17
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    http://en.wikipedia.org/wiki/Self-descriptive_number2011-05-17

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Here is one solution: $$6210001000$$ $$(0123456789)$$

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    I think the problem wants it the other way around.2011-05-17
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    It looks like the request was in the opposite order, 6210001000, which avoids leading zeros.2011-05-17
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    Sloan (http://oeis.org/A108551) claims this solution is unique. Is there an easy way to see this?2011-05-17
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    A more general version of this question came up recently. Put 6210001000 in the search box to see it.2014-06-28