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%I #18 Dec 06 2023 11:24:25
%S 1,11,101,111,1011,1101,1111,10101,10111,11011,11101,11111,101011,
%T 101101,101111,110101,110111,111011,111101,111111,1010101,1010111,
%U 1011011,1011101,1011111,1101011,1101101,1101111,1110101,1110111,1111011,1111101,1111111,10101011,10101101,10101111,10110101,10110111,10111011,10111101
%N Binary numbers that begin and end with 1 and do not contain two adjacent zeros.
%H Chai Wah Wu, <a href="/A247647/b247647.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A007088(A247648(n)).
%t With[{upto=500},Map[FromDigits,Select[IntegerString[Range[1,upto,2],2],StringFreeQ[#,"00"]&]]] (* _Paolo Xausa_, Dec 06 2023 *)
%o (Python)
%o A247647_list = [int(bin(n)[2:]) for n in range(1,10**5) if n % 2 and not '00' in bin(n)]
%o # _Chai Wah Wu_, Sep 25 2014
%o (Haskell)
%o a247647 = a007088 . a247648 -- _Reinhard Zumkeller_, Sep 25 2014
%Y See A247648 for the decimal equivalents.
%Y Cf. A007088, A247649, A253085.
%K nonn,base
%O 1,2
%A _N. J. A. Sloane_, Sep 25 2014
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