A213543 a(n) = n AND 3^n, where AND is the bitwise AND operator.

0, 1, 0, 3, 0, 1, 0, 3, 0, 1, 8, 11, 0, 1, 8, 11, 0, 1, 0, 19, 16, 17, 16, 3, 0, 1, 8, 27, 16, 17, 24, 11, 0, 1, 0, 3, 0, 33, 0, 3, 32, 33, 40, 43, 32, 1, 40, 43, 0, 1, 0, 19, 16, 49, 16, 3, 32, 33, 40, 59, 48, 17, 56, 43, 0, 1, 0, 3, 64, 65, 64, 3, 0, 65, 8, 75

Offset: 0

Author

Alex Ratushnyak, Jun 14 2012

Keywords

• nonn
• base
• easy
• look
• less

Comments

Indices of 0's:

0, 2, 4, 6, 8, 12, 16, 18, 24, 32, 34, 36, 38, 48, 50, 64, 66, 72, 96, 98, 128, 130, 132, 144, 146, 166, 192, 194, 256, 258, 260, 262, 280, 288, 290, 292, 328, 384, 386, 388, 512, 514, ...

Indices of 1's:

1, 5, 9, 13, 17, 25, 33, 45, 49, 65, 89, 97, 129, 173, 177, 193, 257, 261, 265, 281, 353, 385, 513, 517, 521, 529, 561, 601, 685, 705, 769, 773, 777, 1025, 1029, 1037, 1049, 1057, 1073, ...

n's such that a(n)=n:

0, 1, 3, 11, 19, 27, 43, 59, 75, 83, 107, 139, 147, 155, 203, 211, 267, 275, 283, 299, 315, 395, 403, 411, 523, 531, 539, 555, 571, 587, 595, 619, 779, 787, 795, 811, 827, 1051, 1083, ...

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..8192

Crossrefs

Cf. A213526, A213542.

Programs

Maple

a:= proc(n) local i, k, m, r;
      k:= n;
      m:= 3 &^ k mod (2^(1+ilog2(1+k)));
      r:= 0;
      for i from 0 while (m>0 or k>0) do
        r:= r +2^i* irem(m, 2, 'm') *irem(k, 2, 'k')
      od; r
    end:
seq(a(n), n=0..100);  # Alois P. Heinz, Jun 22 2012

Python

print([3**n & n for n in range(99)])