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A131097
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Sum of digits of 3-smooth numbers in ternary representation.
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2
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1, 2, 1, 2, 2, 4, 1, 2, 4, 2, 4, 1, 4, 2, 4, 2, 4, 4, 1, 4, 2, 6, 4, 2, 4, 4, 1, 4, 4, 2, 6, 4, 2, 8, 4, 4, 1, 4, 4, 2, 8, 6, 4, 2, 8, 4, 4, 10, 1, 4, 4, 2, 8, 6, 4, 10, 2, 8, 4, 4, 10, 1, 4, 4, 8, 2, 8, 6, 4, 10, 2, 8, 4, 10, 4, 10, 1, 4, 4, 8, 2, 8, 6, 16, 4, 10, 2, 8, 4, 10, 4
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OFFSET
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1,2
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COMMENTS
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LINKS
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Eric Weisstein's World of Mathematics, Digit Sum
Eric Weisstein's World of Mathematics, Ternary
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MAPLE
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Res:= NULL: N:= 10^6:
for a from 0 to ilog2(N) do
for b from 0 do
v:= 2^a*3^b;
if v > N then break fi;
Res:= Res, v;
od od:
TS:= sort([Res]):
map(t -> convert(convert(t, base, 3), `+`), TS); # Robert Israel, Oct 08 2018
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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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