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A100909
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Concatenate number of occurrences in n of each decimal digit from 0 to 9 and drop leading zeros.
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1
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1000000000, 100000000, 10000000, 1000000, 100000, 10000, 1000, 100, 10, 1, 1100000000, 200000000, 110000000, 101000000, 100100000, 100010000, 100001000, 100000100, 100000010, 100000001, 1010000000, 110000000, 20000000, 11000000
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OFFSET
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0,1
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COMMENTS
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n = 0 is normally represented as the single digit 0, so a(0) = 1000000000. This representation system is inherently ambiguous by disregarding the order of n's digits but without modification will correctly identify those digits for all numbers up to 999999999 decimal; i.e., a(999999999) = 9; and for many beyond (e.g., a(121212121212121212) = a(111222111222222111) = ... = 990000000). However, for any n in which more than 9 of any single digit occur, additional ambiguity is introduced unless some type of grouping is also used (say, parentheses around or bars over a group of consecutive digits when written) so that, for example, (10) is known to represent 9999999999 rather than 8.
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LINKS
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EXAMPLE
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a(12) = 110000000 as 12 consists only of one 1 and one 2, hence the following are concatenated: 0 1 1 0 0 0 0 0 0 0 and dropping the leading 0 gives 110000000 (= a(21) also).
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CROSSREFS
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Cf. A100910 (each number of digit occurrences is a separate term).
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KEYWORD
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base,easy,nonn
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AUTHOR
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STATUS
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approved
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