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A253586
The sum of the i-th ternary digits of n, k, and A(n,k) equals 0 (mod 3) for each i>=0 (leading zeros included); square array A(n,k), n>=0, k>=0, read by antidiagonals.
4
0, 2, 2, 1, 1, 1, 6, 0, 0, 6, 8, 8, 2, 8, 8, 7, 7, 7, 7, 7, 7, 3, 6, 6, 3, 6, 6, 3, 5, 5, 8, 5, 5, 8, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 18, 3, 3, 0, 3, 3, 0, 3, 3, 18, 20, 20, 5, 2, 2, 5, 2, 2, 5, 20, 20, 19, 19, 19, 1, 1, 1, 1, 1, 1, 19, 19, 19, 24, 18, 18, 24, 0, 0, 6, 0, 0, 24, 18, 18, 24
OFFSET
0,2
LINKS
Rémy Sigrist, Colored representation of the table for 0 <= n, k < 3^7 (where the hue is function of T(n, k))
Wikipedia, Set (game)
FORMULA
A(n,k) = A(floor(n/3),floor(k/3))*3+(6-(n mod 3)-(k mod 3) mod 3), A(0,0) = 0.
EXAMPLE
Square array A(n,k) begins:
0, 2, 1, 6, 8, 7, 3, 5, 4, ...
2, 1, 0, 8, 7, 6, 5, 4, 3, ...
1, 0, 2, 7, 6, 8, 4, 3, 5, ...
6, 8, 7, 3, 5, 4, 0, 2, 1, ...
8, 7, 6, 5, 4, 3, 2, 1, 0, ...
7, 6, 8, 4, 3, 5, 1, 0, 2, ...
3, 5, 4, 0, 2, 1, 6, 8, 7, ...
5, 4, 3, 2, 1, 0, 8, 7, 6, ...
4, 3, 5, 1, 0, 2, 7, 6, 8, ...
MAPLE
A:= proc(n, k) local i, j; `if`(n=0 and k=0, 0,
A(iquo(n, 3, 'i'), iquo(k, 3, 'j'))*3 +irem(6-i-j, 3))
end:
seq(seq(A(n, d-n), n=0..d), d=0..14);
CROSSREFS
Column k=0 and row n=0 gives A004488.
Main diagonal gives A001477.
A(n,floor(n/3)) gives A060587.
Sequence in context: A225200 A128706 A375970 * A347621 A318191 A208183
KEYWORD
nonn,base,tabl,look
AUTHOR
Alois P. Heinz, Jan 04 2015
STATUS
approved