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%I #28 Apr 16 2023 08:30:03
%S 1,16,32,128,256,1024,4096,262144,524288,8388608
%N Powers of 2 with exactly one odd decimal digit.
%C Inspired by A068994 (Powers of 2 such that number of odd digits is 0).
%C No additional terms up to 2^10000.
%C No additional terms < 2^500000. - _Chai Wah Wu_, May 22 2016
%C No additional terms < 2^(10^10). - _Michael S. Branicky_, Apr 16 2023
%t 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 *)
%o (Ruby)
%o ary = [1]
%o s = 1
%o (1..10 ** 4).each{|i|
%o s *= 2
%o j = s.to_s.split('').map(&:to_i).select{|i| i % 2 == 1}.size
%o ary << s if j == 1
%o }
%o p ary
%Y Cf. A068994, A272698.
%K nonn,base
%O 1,2
%A _Seiichi Manyama_, May 04 2016
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