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A039369
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Numbers whose base-9 representation has the same nonzero number of 1's and 6's.
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1
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15, 55, 87, 105, 114, 123, 132, 135, 137, 138, 139, 140, 142, 143, 150, 159, 177, 217, 258, 298, 339, 379, 420, 460, 487, 495, 497, 498, 499, 500, 502, 503, 505, 514, 523, 532, 550, 559, 582, 622, 663, 703, 735, 753, 762, 771, 780, 783, 785, 786, 787, 788
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graph;
refs;
listen;
history;
text;
internal format)
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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, a1;
L:= convert(n, base, 9);
a1:= numboccur(1, L);
a1 > 0 and numboccur(6, L)=a1
end proc:
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MATHEMATICA
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Select[Range[1000], DigitCount[#, 9, 1]==DigitCount[#, 9, 6]>0&] (* Harvey P. Dale, Oct 15 2014 *)
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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