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A247700
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Numbers which have d digits "d", whenever one of their digits is "d", ordered by largest digit, then by size of the number.
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1
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1, 22, 122, 212, 221, 333, 1333, 3133, 3313, 3331, 22333, 23233, 23323, 23332, 32233, 32323, 32332, 33223, 33232, 33322, 122333, 123233, 123323, 123332, 132233, 132323, 132332, 133223, 133232, 133322, 212333, 213233, 213323, 213332
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OFFSET
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1,2
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COMMENTS
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This sequence lists the same terms as A108571, but ordered first by the largest digit in the number, then by size. This way, a truncation to the first 1, 5, 80, 14381,... terms is this very same sequence for bases b=2, 3, 4, 5, ...
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LINKS
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EXAMPLE
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In base 2, the only number with this property is a(1) = 1.
In base 3, this property is again satisfied by 1, but also by the 4 additional terms 22, 122, 212 and 221. They are listed "as such" (without conversion from base 3 to base 10) as a(2),...,a(5).
In base 4, there are 75 more terms (involving three digits "3"), listed as a(6),...,a(80).
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PROG
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(PARI) a=[]; for(d=1, 3, n=[10^d\9*d]; for(i=1, #a, t=vector(d+#s=digits(a[i]), j, 10^j)~\10; forvec(v=vector(d, j, [1, #t]), c=0; n=concat(n, vector(#t, j, if(setsearch(v, j), d, s[c++]))*t), 2)); a=concat(a, vecsort(n))); a \\ M. F. Hasler, Sep 25 2014
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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