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A327132
Last cell visited by knight moves on a spirally numbered hexagonal board of edge-length n, moving to the lowest unvisited cell at each step.
2
1, 1, 1, 34, 45, 76, 98, 135, 181, 234, 290, 338, 413, 487, 566, 654, 742, 823, 930, 1051, 1169, 1291, 1414, 1548, 1685, 1813, 1968, 2138, 2304, 2455, 2632, 2815, 3016, 3187, 3388, 3597, 3803, 4026, 4246, 4473, 4714, 4948, 5194, 5447, 5702, 5969, 6244, 6514
OFFSET
1,4
COMMENTS
A hexagonal board of edge-length 3, for example, is numbered spirally as:
.
17--18--19
/
16 6---7---8
/ / \
15 5 1---2 9
\ \ / /
14 4---3 10
\ /
13--12--11
.
In Glinski's hexagonal chess, a knight (N) can move to these (o) cells:
.
. . . . .
. . o o . .
. o . . . o .
. o . . . . o .
. . . . N . . . .
. o . . . . o .
. o . . . o .
. . o o . .
. . . . .
.
a(n) stays constant at 72085 for n >= 177 since 72085 is also the last cell visited by knight moves on a spirally numbered infinite hexagonal board, moving to the lowest unvisited cell at each step.
CROSSREFS
Sequence in context: A302457 A063470 A089715 * A260284 A274189 A275194
KEYWORD
nonn
AUTHOR
Sangeet Paul, Aug 22 2019
STATUS
approved