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A062182
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Harmonic mean of digits is 4.
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1
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4, 36, 44, 63, 288, 346, 364, 436, 444, 463, 634, 643, 828, 882, 2488, 2666, 2848, 2884, 3366, 3446, 3464, 3636, 3644, 3663, 4288, 4346, 4364, 4436, 4444, 4463, 4634, 4643, 4828, 4882, 6266, 6336, 6344, 6363, 6434, 6443, 6626, 6633, 6662, 8248, 8284
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OFFSET
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1,1
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LINKS
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MAPLE
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filter:= proc(n) local L;
L:= convert(n, base, 10);
if has(L, 0) then return false fi;
nops(L)/add(1/i, i=L)=4
end proc:
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MATHEMATICA
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Do[ h = IntegerDigits[n]; If[ Sort[h][[1]] != 0 && Length[h]/Apply[Plus, 1/h] == 4, Print[n]], {n, 1, 10^5}]
hm4Q[n_]:=DigitCount[n, 10, 0]==0&&HarmonicMean[IntegerDigits[n]]==4; Select[Range[9000], hm4Q] (* Harvey P. Dale, Mar 23 2011 *)
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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