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%I #10 Nov 08 2013 17:33:19
%S 1,10,11,101,110,111,1001,1010,1011,1101,1110,1111,10001,10010,10011,
%T 10101,10110,10111,11001,11010,11101,11110,11111,100001,100010,100011,
%U 100101,100110,100111,101001,101010,101011,101101,101110,101111,110001
%N Squarefree numbers containing in their decimal representation only the digits 0 and 1.
%H Reinhard Zumkeller, <a href="/A077813/b077813.txt">Table of n, a(n) for n = 1..10000</a>
%e a(51) = 1000110 = 2*3*5*17*37*53.
%t Union[Select[FromDigits/@Tuples[{1,0},6],SquareFreeQ]] (* _Harvey P. Dale_, Nov 07 2013 *)
%o (Haskell)
%o a077813 n = a077813_list !! (n-1)
%o a077813_list = filter ((== 1) . a008966) $ tail $
%o map ((foldr (\d v -> v * 10 + d) 0) . map fromIntegral) a030308_tabf
%o -- _Reinhard Zumkeller_, Nov 08 2013
%Y Cf. A077812, A020449, A005117.
%Y Cf. A008966, A030308.
%K nonn,base
%O 1,2
%A _Reinhard Zumkeller_, Nov 16 2002
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