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A362326
Pairs (i, j) of nonnegative integers whose ternary expansions have no common digit 1 sorted first by i + j then by i.
3
0, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 3, 1, 2, 2, 1, 3, 0, 0, 4, 1, 3, 2, 2, 3, 1, 4, 0, 0, 5, 2, 3, 3, 2, 5, 0, 0, 6, 1, 5, 2, 4, 4, 2, 5, 1, 6, 0, 0, 7, 1, 6, 2, 5, 5, 2, 6, 1, 7, 0, 0, 8, 2, 6, 6, 2, 8, 0, 0, 9, 1, 8, 2, 7, 3, 6, 6, 3, 7, 2, 8, 1, 9, 0, 0, 10
OFFSET
1,8
COMMENTS
This sequence is to Sierpinski carpet what A352909 is to Sierpinski gasket.
There are A293974(n + 1) pairs (i, j) with n = i + j.
See A362329 for the other pairs.
EXAMPLE
The first pairs are:
(0, 0),
(0, 1), (1, 0),
(0, 2), (2, 0),
(0, 3), (1, 2), (2, 1), (3, 0),
(0, 4), (1, 3), (2, 2), (3, 1), (4, 0),
(0, 5), (2, 3), (3, 2), (5, 0),
(0, 6), (1, 5), (2, 4), (4, 2), (5, 1), (6, 0),
(0, 7), (1, 6), (2, 5), (5, 2), (6, 1), (7, 0),
(0, 8), (2, 6), (6, 2), (8, 0),
...
PROG
(PARI) is(i, j) = { while (i && j, if (i%3==1 && j%3==1, return (0), i\=3; j\=3; ); ); return (1); }
row(ij) = apply (i -> [i, ij-i], select(i -> is(i, ij-i), [0..ij]))
CROSSREFS
Cf. A293974, A352909, A362327 (i-values), A362328 (j-values), A362329 (complement).
Sequence in context: A300333 A357019 A352562 * A352909 A323473 A341288
KEYWORD
nonn,tabf,base
AUTHOR
Rémy Sigrist, Apr 16 2023
STATUS
approved