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%I #19 May 13 2016 16:27:45
%S 0,14,134,4102,87112285931760246646623899502532662132742,
%T 1852673427797059126777135760139006525652319754650249024631321344126610074239106
%N a(n) is the smallest even number which has n inverse images under the map x -> x + (binary weight of x).
%C If the word "even" is omitted the sequence is A230303.
%C The next term is a(7) = 2^4233 + 130.
%e The smallest number with two inverses is 14: the inverses are 11 = 1011_2 which maps to 11+3 = 14, and 12 = 1100_2 which maps to 12+2 = 14.
%Y Cf. A230303, A000120, A092391, A228085.
%K nonn
%O 1,2
%A _Max Alekseyev_ and _N. J. A. Sloane_, May 13 2016