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%I #8 Nov 17 2019 01:30:23
%S 0,2,4,6,3,10,103,9,5,18
%N a(n) = smallest d such that the sum of digits of 2^d - n is equal to d, or -1 if no such d exists.
%C The first open case is 11. Is a(11) = -1? See A329493.
%C If a(i) = m > 0 then A328882 takes the value -i for the first time at term 2^m-i. For example, the first appearance of -7 in A328882 is at term 2^103 - 7.
%Y Cf. A328882, A329002, A329493.
%K nonn,base,more
%O 1,2
%A _N. J. A. Sloane_, Nov 16 2019