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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row lengths are A279402.

LINKS

Table of n, a(n) for n=1..65.

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

Cf. A279402, A279406.

Sequence in context: A070444 A120866 A070443 * A070643 A070442 A086957

Adjacent sequences:  A279400 A279401 A279402 * A279404 A279405 A279406

KEYWORD

nonn,tabf

AUTHOR

Andrey Zabolotskiy, Dec 11 2016

STATUS

approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)