%I #13 Oct 14 2019 03:58:41
%S 5,8,9,17,21
%N Numbers k such that 2^k contains 2^1=2 as its largest proper substring of the form 2^m (probably finite).
%Y Cf. A033921.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Jun 15 1998
