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A101813
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Odd Niven (or Harshad) numbers: odd numbers that are divisible by the sum of their digits.
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2
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1, 3, 5, 7, 9, 21, 27, 45, 63, 81, 111, 117, 133, 135, 153, 171, 195, 201, 207, 209, 225, 243, 247, 261, 285, 315, 333, 351, 375, 399, 405, 407, 423, 441, 465, 481, 511, 513, 531, 555, 603, 605, 621, 629, 645, 711, 715, 735, 777, 801, 803, 825, 915, 935, 999
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OFFSET
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1,2
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REFERENCES
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David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, p. 171.
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LINKS
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EXAMPLE
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629 is a term of the sequence because it is odd and divisible by 17 (= 6+2+9).
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MAPLE
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s:=proc(n) local N:N:=convert(n, base, 10):sum(N[j], j=1..nops(N)) end:p:=proc(n) if floor(n/s(n))=n/s(n) then n else fi end: seq(p(2*n-1), n=1..530);
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MATHEMATICA
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Select[Range[1, 999, 2], Divisible[#, Total[IntegerDigits[#]]]&] (* Harvey P. Dale, Aug 22 2011 *)
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PROG
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(PARI) isok(n) = (n%2) && !(n % sumdigits(n)); \\ Michel Marcus, Sep 19 2017
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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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EXTENSIONS
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STATUS
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approved
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