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A368212
Square spiral of positive integers built by greedy algorithm such that each value corresponds to the area of the connected component with terms of the same value and containing this value.
1
1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 2, 3, 1, 3, 2, 3, 1, 3, 2, 3, 1, 3, 2, 3, 1, 2, 3, 1, 3, 2, 1, 2, 3, 1, 3, 2, 1, 2, 3, 1, 3, 2, 1, 2, 3, 1, 3, 2, 1, 3, 2, 3, 2, 3, 2, 3, 1, 3, 2, 3, 2, 3, 2, 3, 1, 3, 2, 3, 2, 3, 2, 3, 1, 3, 2, 3, 2, 3, 2, 3, 1, 2, 3, 1, 4, 2, 1
OFFSET
0,2
COMMENTS
In other words, we tile the plane with polyominoes as small as possible, and for any k > 0, two k-ominoes cannot share an edge.
This sequence is a variant of A368148.
Empirically, the spiral has 4-fold rotational symmetry.
EXAMPLE
The spiral begins:
1---3---2---3---1
| |
3 1---2---1 3
| | | |
2 2 1---2 2
| | |
3 1---2---1---3
|
1---3---2---3---1
PROG
(PARI) \\ See Links section.
CROSSREFS
Cf. A368148.
Sequence in context: A309025 A247599 A083897 * A025823 A025821 A161233
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Dec 17 2023
STATUS
approved