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A272697
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Powers of 2 with exactly one odd decimal digit.
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0
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OFFSET
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1,2
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COMMENTS
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Inspired by A068994 (Powers of 2 such that number of odd digits is 0).
No additional terms up to 2^10000.
No additional terms < 2^500000. - Chai Wah Wu, May 22 2016
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LINKS
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MATHEMATICA
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Select[2^Range[0, 50000], Total@ Pick[DigitCount@ #, {1, 0, 1, 0, 1, 0, 1, 0, 1, 0}, 1] == 1 &] (* Michael De Vlieger, May 04 2016 *)
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PROG
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(Ruby)
ary = [1]
s = 1
(1..10 ** 4).each{|i|
s *= 2
j = s.to_s.split('').map(&:to_i).select{|i| i % 2 == 1}.size
ary << s if j == 1
}
p ary
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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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