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A188341
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Numbers having no 0's and not more than one 1 in their representation in base 3.
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8
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1, 2, 5, 7, 8, 17, 23, 25, 26, 53, 71, 77, 79, 80, 161, 215, 233, 239, 241, 242, 485, 647, 701, 719, 725, 727, 728, 1457, 1943, 2105, 2159, 2177, 2183, 2185, 2186, 4373, 5831, 6317, 6479, 6533, 6551, 6557, 6559, 6560, 13121, 17495, 18953
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refs;
listen;
history;
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internal format)
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OFFSET
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1,2
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LINKS
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Alois P. Heinz, Table of n, a(n) for n = 1..1000
V. Shevelev, Binomial Coefficient Predictors, Journal of Integer Sequences, Vol. 14 (2011), Article 11.2.8
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MAPLE
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a:= proc(n) option remember; local i, l, m, t;
m:= `if`(n=1, 0, a(n-1));
l:= NULL;
for t while m>0 do l:= l, irem(m, 3, 'm') od;
l:= array([l, 0]);
for i while l[i]=2 do od;
if l[i]=0 then l[i]:= 1
else l[i]:= 2;
if i>1 then l[i-1]:= 1 fi
fi;
add(l[i] *3^(i-1), i=1..t)
end:
seq(a(n), n=1..100); # Alois P. Heinz, Apr 02 2011
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MATHEMATICA
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okQ[n_]:=DigitCount[n, 3, 0]==0&&DigitCount[n, 3, 1]<2; Select[Range[20000], okQ] (* Harvey P. Dale, Apr 16 2011 *)
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CROSSREFS
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Cf. A062756, A077267.
Sequence in context: A275410 A139481 A340326 * A238364 A342730 A227445
Adjacent sequences: A188338 A188339 A188340 * A188342 A188343 A188344
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KEYWORD
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nonn,base
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AUTHOR
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Vladimir Shevelev, Apr 02 2011
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STATUS
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approved
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