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%I #8 Sep 01 2020 07:39:26
%S 10,11,100,111,1000,1010,1101,1111,10000,10010,10100,10110,11001,
%T 11011,11101,11111,100000,100010,100100,100110,101000,101010,101100,
%U 101110,110001,110011,110101,110111,111001,111011,111101,111111,1000000,1000010,1000100,1000110
%N Binary expansion of numbers in A171781.
%H Amiram Eldar, <a href="/A171782/b171782.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A007088(A171781(n)). - _Amiram Eldar_, Sep 01 2020
%t bin[n_] := FromDigits[IntegerDigits[n, 2]]; bin /@ Select[Range[2, 70], (d = IntegerDigits[#, 2])[[2]] == d[[-1]] &] (* _Amiram Eldar_, Sep 01 2020 *)
%Y Cf. A007088, A171781.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, Oct 12 2010