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A171823 a(n) = base-2 concatenation XYZ, where X = number of bits in binary expansion of n, Y = number of 0's, Z = number of 1's. 2
101, 1011, 10010, 11101, 11110, 11110, 11011, 100111, 1001010, 1001010, 100111, 1001010, 100111, 100111, 1000100, 1011001, 1011110, 1011110, 1011011, 1011110, 1011011, 1011011, 1011100, 1011110, 1011011, 1011011, 1011100, 1011011, 1011100, 1011100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..30.

EXAMPLE

14 = 1110 in base 2, so X = 4 = 100, Y = 1, Z = 3 = 11, a(14) = 100.1.11 = 100111.

MAPLE

F:=proc(n) local t1, t2, t2b, n1, n1b, n0, n0b, t3, t4;

t1:=convert(n, base, 2);

t2:=nops(t1);

t2b:=convert(t2, base, 2);

n1:=add(t1[i], i=1..t2);

n1b:=convert(n1, base, 2);

n0:=t2-n1;

n0b:=convert(n0, base, 2);

t3:=[

seq(t2b[nops(t2b)+1-i], i=1..nops(t2b)),

seq(n0b[nops(n0b)+1-i], i=1..nops(n0b)),

seq(n1b[nops(n1b)+1-i], i=1..nops(n1b))

];

t4:="";

for i from 1 to nops(t3) do t4:=cat(t4, t3[i]); od:

parse(t4);

end;

MATHEMATICA

a[n_] := IntegerDigits[{z, y} = DigitCount[n, 2]; {y+z, y, z}, 2] // Flatten // FromDigits; Array[a, 30] (* Jean-Fran├žois Alcover, Oct 20 2016 *)

CROSSREFS

Cf. A171825, A171798, A171813.

Sequence in context: A289578 A190619 A290197 * A289528 A289771 A131194

Adjacent sequences:  A171820 A171821 A171822 * A171824 A171825 A171826

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Oct 16 2010

STATUS

approved

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Last modified July 22 16:43 EDT 2019. Contains 325225 sequences. (Running on oeis4.)