|
%I #21 Dec 21 2022 20:12:34
%S 1,0,1,0,11,10,1,0,111,110,101,100,11,10,1,0,1111,1110,1101,1100,1011,
%T 1010,1001,1000,111,110,101,100,11,10,1,0,11111,11110,11101,11100,
%U 11011,11010,11001,11000,10111,10110,10101,10100,10011,10010,10001,10000
%N Write n in binary, exchange digits '0' <-> '1'.
%C Binary representation of A035327.
%C A base-2 analog of A048379.
%t Table[FromDigits[IntegerDigits[n, 2] /. {0 -> 1, 1 -> 0}], {n, 0, 47}] (* or *)
%t Table[FromDigits@ IntegerDigits[BitXor[n, 2^IntegerPart[Log[2, n] + 1] - 1], 2], {n, 0, 47}] (* _Michael De Vlieger_, Mar 22 2015, the latter based on _Alonso del Arte_ at A035327 *)
%o (PARI) A256078(n)=!n+eval(Strchr(apply(d->49-d,binary(n))))
%o (Python)
%o def a(n): return int(bin(1 if n==0 else n^((1 << n.bit_length())-1))[2:])
%o print([a(n) for n in range(48)]) # _Michael S. Branicky_, Dec 21 2022
%Y Cf. A035327, A048379.
%K nonn,base,easy
%O 0,5
%A _M. F. Hasler_, Mar 22 2015
|
