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A058898
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Inconsummate numbers in base 2: no number is this multiple of the sum of its digits (in base 2).
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16
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13, 19, 25, 26, 35, 38, 47, 49, 50, 52, 55, 67, 70, 76, 94, 95, 97, 98, 100, 103, 104, 109, 110, 115, 117, 131, 134, 140, 151, 152, 157, 159, 171, 175, 179, 183, 185, 187, 188, 190, 193, 194, 196, 199, 200, 203, 206, 208, 217, 218, 220, 227, 229
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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COMMENTS
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Equivalently, these are the natural numbers that cannot be written as the arithmetic mean of distinct powers of 2. - Brian Kell, Feb 28 2009
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LINKS
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FORMULA
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MAPLE
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MATHEMATICA
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Do[k = n; While[ Apply[ Plus, IntegerDigits[k, 2] ]*n != k && k < 250n, k += n]; If[k == 250n, Print[n] ], {n, 1, 10^3} ]
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PROG
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(Python)
from itertools import count, islice, combinations_with_replacement
def A058898_gen(startvalue=1): # generator of terms >= startvalue
for n in count(max(startvalue, 1)):
for l in count(1):
if l*n < 1<<l-1:
yield n
break
for d in combinations_with_replacement((0, 1), l):
if (s:=sum(d))>0 and sorted(bin(s*n)[2:]) == [str(e) for e in d]:
break
else:
continue
break
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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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STATUS
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approved
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