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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. – Raskolnikov May 17 '11 at 17:50
thank you very much. – Ondrej Sotolar May 17 '11 at 17:56

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

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I think the problem wants it the other way around. – Listing May 17 '11 at 18:03
It looks like the request was in the opposite order, 6210001000, which avoids leading zeros. – Ross Millikan May 17 '11 at 18:04
Sloan ( claims this solution is unique. Is there an easy way to see this? – Nate Eldredge May 17 '11 at 19:08
A more general version of this question came up recently. Put 6210001000 in the search box to see it. – Robert Soupe Jun 28 '14 at 16:30

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