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A066489 Binary expansion of n followed by its reverse complement. 0

%I #8 Oct 22 2023 17:53:22

%S 10,1010,1100,100110,101010,110100,111000,10001110,10010110,10101010,

%T 10110010,11001100,11010100,11101000,11110000,1000011110,1000101110,

%U 1001010110,1001100110,1010011010,1010101010,1011010010,1011100010,1100011100,1100101100,1101010100

%N Binary expansion of n followed by its reverse complement.

%e a(2) = 1010 because 2 in binary is 10, the complement of which is 01, the reverse of which is 10, hence (10)(10). - _Sean A. Irvine_, Oct 22 2023

%p a:= n-> (l-> parse(cat(seq(l[-i], i=1..nops(l)), 1-~l[])))(Bits[Split](n)):

%p seq(a(n), n=1..30); # _Alois P. Heinz_, Oct 22 2023

%o (PARI) a(n)={my(v=binary(n)); fromdigits(concat(v,vector(#v,i,1-v[#v+1-i])))} \\ _Andrew Howroyd_, Oct 22 2023

%Y Binary expansion of numbers in A035928.

%K base,easy,nonn

%O 1,1

%A _John McNamara_, Jan 09 2002

%E Title clarified and more terms from _Sean A. Irvine_, Oct 22 2023

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Last modified July 30 22:55 EDT 2024. Contains 374771 sequences. (Running on oeis4.)