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A257296
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Arithmetic mean of the digits of n, multiplied by 10^(d-1) and rounded down, where d is the number of digits of n.
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1
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 30, 35, 40, 45, 50, 55, 60, 65
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OFFSET
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0,3
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COMMENTS
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The reason for the factor 10^(d-1) in the definition is to produce an analog of A257294, i.e., give the first d digits of the mean value, for an "average" d-digit number. But since the arithmetic mean of the digits may be between 0 and 1, the situation is slightly different from the case of the geometric mean.
Also motivated by sequence A257829.
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LINKS
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FORMULA
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EXAMPLE
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For n = 12, a two-digit number, the average of the digits is 1.50000..., so a(12) = 15.
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MAPLE
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f:= proc(n) local d;
d:= ilog10(n);
floor(convert(convert(n, base, 10), `+`)/(d+1)*10^d)
end proc:
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MATHEMATICA
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Table[Floor[Mean[IntegerDigits[n]]10^(IntegerLength[n]-1)], {n, 0, 70}] (* Harvey P. Dale, Mar 11 2020 *)
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PROG
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(PARI) a(n)=sum(i=1, #n=digits(n), n[i])*10^(#n-1)\#n
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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