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A289869 Square array T(n,k) (n>=0, k>=0) read by antidiagonals downwards: T(n,k) = A005836(n) + 2*A005836(k). 2
0, 2, 1, 6, 3, 3, 8, 7, 5, 4, 18, 9, 9, 6, 9, 20, 19, 11, 10, 11, 10, 24, 21, 21, 12, 15, 12, 12, 26, 25, 23, 22, 17, 16, 14, 13, 54, 27, 27, 24, 27, 18, 18, 15, 27, 56, 55, 29, 28, 29, 28, 20, 19, 29, 28, 60, 57, 57, 30, 33, 30, 30, 21, 33, 30, 30, 62, 61, 59 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If n and k have no common one bit in base 2 representation (n AND k = 0), then n = A289813(T(n,k)) and k = A289814(T(n,k)).

This sequence, when restricted to the pairs of numbers without common bits in base 2 representation, is the inverse of the function n -> (A289813(n), A289814(n)).

LINKS

Rémy Sigrist, First 100 antidiagonals of array, flattened

EXAMPLE

The table begins:

x\y:    0   1   2   3   4   5   6   7   8   9  ...

0:      0   2   6   8   18  20  24  26  54  56 ...

1:      1   3   7   9   19  21  25  27  55  57 ...

2:      3   5   9   11  21  23  27  29  57  59 ...

3:      4   6   10  12  22  24  28  30  58  60 ...

4:      9   11  15  17  27  29  33  35  63  65 ...

5:      10  12  16  18  28  30  34  36  64  66 ...

6:      12  14  18  20  30  32  36  38  66  68 ...

7:      13  15  19  21  31  33  37  39  67  69 ...

8:      27  29  33  35  45  47  51  53  81  83 ...

9:      28  30  34  36  46  48  52  54  82  84 ...

...

PROG

(PARI) T(n, k) = fromdigits(binary(n), 3) + 2*fromdigits(binary(k), 3)

(Python)

def T(n, k): return int(bin(n)[2:], 3) + 2*int(bin(k)[2:], 3)

for n in xrange(11): print [T(k, n - k) for k in xrange(n + 1)] # Indranil Ghosh, Aug 03 2017

CROSSREFS

Cf. A005836, A289813, A289814.

Sequence in context: A121281 A232467 A131449 * A124443 A077172 A160047

Adjacent sequences:  A289866 A289867 A289868 * A289870 A289871 A289872

KEYWORD

nonn,tabl,base

AUTHOR

Rémy Sigrist, Jul 14 2017

STATUS

approved

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Last modified February 22 18:00 EST 2018. Contains 299469 sequences. (Running on oeis4.)