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A308881 Irregular array read by rows: row k (k>=1) contains k^2 numbers, formed by filling in a k X k square by upwards antidiagonals so entries in all rows, columns, diagonals, antidiagonals are distinct, and then reading that square across rows. 2
0, 0, 2, 1, 3, 0, 2, 1, 1, 3, 4, 2, 0, 5, 0, 2, 1, 5, 1, 3, 4, 0, 2, 0, 5, 1, 3, 1, 2, 4, 0, 2, 1, 5, 3, 1, 3, 4, 0, 6, 2, 0, 5, 1, 7, 3, 1, 2, 4, 0, 4, 5, 0, 3, 1, 0, 2, 1, 5, 3, 4, 1, 3, 4, 0, 7, 2, 2, 0, 5, 1, 6, 9, 3, 1, 2, 4, 0, 5, 4, 6, 0, 3, 1, 7, 5, 7, 8, 6, 4, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
The first row of the k X k square converges to A295563 as k increases.
When filling in the k X k square, always choose the smallest possible number. Each k X k square is uniquely determined.
LINKS
F. Michel Dekking, Jeffrey Shallit, and N. J. A. Sloane, Queens in exile: non-attacking queens on infinite chess boards, Electronic J. Combin., 27:1 (2020), #P1.52.
EXAMPLE
The first eight squares are (here A=10, B=11, C=12):
0
--------
02
13
--------
021
134
205
--------
0215
1340
2051
3124
--------
02153
13406
20517
31240
45031
--------
021534
134072
205169
312405
460317
57864A
--------
0215349
1340725
2051864
3124058
4603172
5786493
6432587
--------
0215349A
13407258
20518643
31240786
4603152B
5786493C
64325879
756893A2
--------
CROSSREFS
Sequence in context: A125073 A350387 A325310 * A281488 A071461 A091829
KEYWORD
nonn,tabf
AUTHOR
N. J. A. Sloane, Jun 29 2019
STATUS
approved

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Last modified April 23 02:23 EDT 2024. Contains 371906 sequences. (Running on oeis4.)