A344836 Square array T(n, k), n, k >= 0, read by antidiagonals; T(n, k) = (n * 2^max(0, w(k)-w(n))) XOR (k * 2^max(0, w(n)-w(k))) (where XOR denotes the bitwise XOR operator and w = A070939).

0, 1, 1, 2, 0, 2, 3, 0, 0, 3, 4, 1, 0, 1, 4, 5, 0, 1, 1, 0, 5, 6, 1, 0, 0, 0, 1, 6, 7, 2, 1, 2, 2, 1, 2, 7, 8, 3, 2, 3, 0, 3, 2, 3, 8, 9, 0, 3, 0, 1, 1, 0, 3, 0, 9, 10, 1, 0, 1, 2, 0, 2, 1, 0, 1, 10, 11, 2, 1, 4, 3, 3, 3, 3, 4, 1, 2, 11, 12, 3, 2, 5, 0, 2, 0, 2, 0, 5, 2, 3, 12

Offset: 0

Author

Rémy Sigrist, May 29 2021

Keywords

• nonn
• base
• tabl

Comments

In other words, we right pad the binary expansion of the lesser of n and k with zeros (provided it is positive) so that both numbers have the same number of binary digits, and then apply the bitwise XOR operator.

Examples

			Array T(n, k) begins:
  n\k|   0  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15
  ---+-------------------------------------------------------
    0|   0  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15
    1|   1  0  0  1  0  1  2  3  0  1   2   3   4   5   6   7
    2|   2  0  0  1  0  1  2  3  0  1   2   3   4   5   6   7
    3|   3  1  1  0  2  3  0  1  4  5   6   7   0   1   2   3
    4|   4  0  0  2  0  1  2  3  0  1   2   3   4   5   6   7
    5|   5  1  1  3  1  0  3  2  2  3   0   1   6   7   4   5
    6|   6  2  2  0  2  3  0  1  4  5   6   7   0   1   2   3
    7|   7  3  3  1  3  2  1  0  6  7   4   5   2   3   0   1
    8|   8  0  0  4  0  2  4  6  0  1   2   3   4   5   6   7
    9|   9  1  1  5  1  3  5  7  1  0   3   2   5   4   7   6
   10|  10  2  2  6  2  0  6  4  2  3   0   1   6   7   4   5
   11|  11  3  3  7  3  1  7  5  3  2   1   0   7   6   5   4
   12|  12  4  4  0  4  6  0  2  4  5   6   7   0   1   2   3
   13|  13  5  5  1  5  7  1  3  5  4   7   6   1   0   3   2
   14|  14  6  6  2  6  4  2  0  6  7   4   5   2   3   0   1
   15|  15  7  7  3  7  5  3  1  7  6   5   4   3   2   1   0
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..10010
• Rémy Sigrist, Colored representation of the table for n, k < 2^10

Crossrefs

Cf. A003987, A053645, A070939.

Cf. A344834 (AND), A344835 (OR), A344837 (min), A344838 (max), A344839 (absolute difference).

Programs

PARI

T(n, k, op=bitxor, w=m->#binary(m)) = { op(n*2^max(0, w(k)-w(n)), k*2^max(0, w(n)-w(k))) }

Formula

T(n, k) = T(k, n).

T(n, n) = 0.

T(n, 0) = n.

T(n, 1) = A053645(n) for any n > 0.