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%I #23 Oct 13 2023 14:03:08
%S 1,3,7,9,19,21,43,45,55,57,115,117,127,129,259,261,271,273,331,333,
%T 343,345,691,693,703,705,763,765,775,777,1555,1557,1567,1569,1627,
%U 1629,1639,1641,1987,1989,1999,2001,2059,2061,2071,2073
%N Numbers whose set of base-6 digits is {1,3}.
%H Vincenzo Librandi, <a href="/A032913/b032913.txt">Table of n, a(n) for n = 1..1000</a>
%t Flatten[Table[FromDigits[#,6]&/@Tuples[{1,3},n],{n,5}]] (* _Harvey P. Dale_, Nov 16 2011 *)
%o (Magma) [n: n in [1..2500] | Set(IntegerToSequence(n, 6)) subset {1, 3}]; // _Vincenzo Librandi_, Jun 01 2012
%o (Python)
%o def A032913(n): return (int(bin(m:=n+1)[3:],6)<<1) + (6**(m.bit_length()-1)-1)//5 # _Chai Wah Wu_, Oct 13 2023
%Y Cf. A007092, A032917.
%K nonn,base
%O 1,2
%A _Clark Kimberling_
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