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A067138
OR-numbral multiplication table, read by antidiagonals.
12
0, 0, 0, 0, 1, 0, 0, 2, 2, 0, 0, 3, 4, 3, 0, 0, 4, 6, 6, 4, 0, 0, 5, 8, 7, 8, 5, 0, 0, 6, 10, 12, 12, 10, 6, 0, 0, 7, 12, 15, 16, 15, 12, 7, 0, 0, 8, 14, 14, 20, 20, 14, 14, 8, 0, 0, 9, 16, 15, 24, 21, 24, 15, 16, 9, 0, 0, 10, 18, 24, 28, 30, 30, 28, 24, 18, 10, 0, 0, 11, 20, 27, 32, 31, 28
OFFSET
0,8
COMMENTS
See A048888 for the definition of OR-numbral arithmetic
FORMULA
From Rémy Sigrist, Mar 17 2021: (Start)
T(n, 0) = 0.
T(n, 1) = n.
T(n, 2^k) = n*2^k for any k >= 0.
T(n, n) = A067398(n).
(End)
For all n, k: A048720(n,k) <= A(n,k) <= A004247(n,k). - Antti Karttunen, Mar 17 2021
EXAMPLE
The top left 0..16 x 0..16 corner of the array:
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30,
0, 3, 6, 7, 12, 15, 14, 15, 24, 27, 30, 31, 28, 31, 30, 31,
0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60,
0, 5, 10, 15, 20, 21, 30, 31, 40, 45, 42, 47, 60, 61, 62, 63,
0, 6, 12, 14, 24, 30, 28, 30, 48, 54, 60, 62, 56, 62, 60, 62,
0, 7, 14, 15, 28, 31, 30, 31, 56, 63, 62, 63, 60, 63, 62, 63,
0, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120,
0, 9, 18, 27, 36, 45, 54, 63, 72, 73, 90, 91, 108, 109, 126, 127,
0, 10, 20, 30, 40, 42, 60, 62, 80, 90, 84, 94, 120, 122, 124, 126,
0, 11, 22, 31, 44, 47, 62, 63, 88, 91, 94, 95, 124, 127, 126, 127,
0, 12, 24, 28, 48, 60, 56, 60, 96, 108, 120, 124, 112, 124, 120, 124,
0, 13, 26, 31, 52, 61, 62, 63, 104, 109, 122, 127, 124, 125, 126, 127,
0, 14, 28, 30, 56, 62, 60, 62, 112, 126, 124, 126, 120, 126, 124, 126,
0, 15, 30, 31, 60, 63, 62, 63, 120, 127, 126, 127, 124, 127, 126, 127,
0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240,
.
Multiplying 3 ("11" in binary) with itself in this system means taking bitwise-or of "11" with itself, when shifted one bit-position left:
11
110
-------
OR: 111 = 7 in decimal = A(3,3).
.
Multiplying 10 (= "1010" in binary) and 11 (= "1011" in binary) in this system means taking bitwise-or of binary number 1011 when shifted once left with the same binary number when shifted three bit-positions left:
10110
1011000
-------
OR: 1011110 = 94 in decimal = A(10,11) = A(11,10).
PROG
(PARI) t(n, k) = {res = 0; for (i=0, length(binary(n))-1, if (bittest(n, i), res = bitor(res, shift(k, i))); ); return (res); } \\ Michel Marcus, Apr 14 2013
CROSSREFS
Cf. A003986, A067139, A048888, A007059, A067398 (main diagonal).
Cf. also A004247, A048720 for analogous multiplication tables.
Sequence in context: A063711 A057893 A048720 * A059692 A353109 A336225
KEYWORD
nonn,tabl,look
AUTHOR
Jens Voß, Jan 02 2002
EXTENSIONS
Example-section rewritten by Antti Karttunen, Mar 17 2021
STATUS
approved