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A279403
Irregular triangle read by rows: T(n,k) (n>=1, 0 <= k <= n^2) = minimal number of squares not attacked by k queens on an n X n toroidal board, with trailing zeros truncated.
2
1, 4, 9, 16, 4, 25, 8, 2, 36, 16, 4, 49, 24, 11, 4, 64, 36, 16, 6, 81, 48, 27, 12, 3, 100, 64, 36, 19, 4, 121, 80, 51, 29, 13, 144, 100, 64, 39, 16, 6, 169, 120, 83, 53, 29, 8, 2, 196, 144, 100, 67, 36, 18, 8, 225, 168, 223, 82, 41, 256, 196, 144, 103, 64, 40
OFFSET
1,2
COMMENTS
Row lengths are A279402.
FORMULA
T(n,0) = A000290(n).
T(n,1) = A000290(n)-A047461(n) = A137932(n-1).
T(n,2) = A248825(n-4) for n >= 6.
EXAMPLE
The triangle begins:
1 (0)
4 (0, 0, 0, 0)
9 (0, 0, ...)
16 4 (0, 0, ...)
25 8 2
36 16 4
49 24 11 4
64 36 16 6
81 48 27 12 3
100 64 36 19 4
121 80 51 29 13
144 100 64 39 16 6
169 120 83 53 29 8 2
196 144 100 67 36 18 8
225 168 123 82 41
256 196 144 103 64 40 ...
CROSSREFS
Sequence in context: A070444 A120866 A070443 * A330377 A070643 A070442
KEYWORD
nonn,tabf
AUTHOR
Andrey Zabolotskiy, Dec 11 2016
STATUS
approved