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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

%I #10 Jun 08 2017 16:33:48

%S 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,

%T 36,19,4,121,80,51,29,13,144,100,64,39,16,6,169,120,83,53,29,8,2,196,

%U 144,100,67,36,18,8,225,168,223,82,41,256,196,144,103,64,40

%N 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.

%C Row lengths are A279402.

%F T(n,0) = A000290(n).

%F T(n,1) = A000290(n)-A047461(n) = A137932(n-1).

%F T(n,2) = A248825(n-4) for n >= 6.

%e The triangle begins:

%e 1 (0)

%e 4 (0, 0, 0, 0)

%e 9 (0, 0, ...)

%e 16 4 (0, 0, ...)

%e 25 8 2

%e 36 16 4

%e 49 24 11 4

%e 64 36 16 6

%e 81 48 27 12 3

%e 100 64 36 19 4

%e 121 80 51 29 13

%e 144 100 64 39 16 6

%e 169 120 83 53 29 8 2

%e 196 144 100 67 36 18 8

%e 225 168 123 82 41

%e 256 196 144 103 64 40 ...

%Y Cf. A279402, A279406.

%K nonn,tabf

%O 1,2

%A _Andrey Zabolotskiy_, Dec 11 2016

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Last modified April 24 11:01 EDT 2024. Contains 371936 sequences. (Running on oeis4.)