cp's OEIS Frontend

A216196 A diagonalized Sudoku torus.

%I A216196 #13 Apr 19 2013 10:28:36
%S A216196 1,2,3,4,5,6,7,8,9,6,5,4,9,8,7,3,2,1,7,8,9,1,2,3,4,5,6,2,3,1,5,6,4,8,
%T A216196 9,7,4,6,5,7,9,8,1,3,2,8,9,7,2,3,1,5,6,4,3,1,2,6,4,5,9,7,8,5,4,6,8,7,
%U A216196 9,2,1,3,9,7,8,3,1,2,6,4,5
%N A216196 A diagonalized Sudoku torus.
%C A216196 This Sudoku contains 27 (internal and external) diagonals.
%C A216196 Conjecture: This is the maximum for a Xoox-free grid.
%C A216196 More are possible (45 in the example) if the grid is allowed to contain Xoox's (ambiguous Sudoku's).
%e A216196 1 2 3 4 5 6 7 8 9
%e A216196 6 5 4 9 8 7 3 2 1
%e A216196 7 8 9 1 2 3 4 5 6
%e A216196 2 3 1 5 6 4 8 9 7
%e A216196 4 6 5 7 9 8 1 3 2
%e A216196 8 9 7 2 3 1 5 6 4
%e A216196 3 1 2 6 4 5 9 7 8
%e A216196 5 4 6 8 7 9 2 1 3
%e A216196 9 7 8 3 1 2 6 4 5
%e A216196 A Xoox is for example:
%e A216196 14
%e A216196 41
%e A216196 and is not necessarily adjacent.
%e A216196 This grid:
%e A216196 1 8 3 4 2 6 7 5 9
%e A216196 6 5 4 9 8 7 3 2 1
%e A216196 7 2 9 1 5 3 4 8 6
%e A216196 2 9 1 5 3 4 8 6 7
%e A216196 4 6 5 7 9 8 1 3 2
%e A216196 8 3 7 2 6 1 5 9 4
%e A216196 3 7 2 6 1 5 9 4 8
%e A216196 5 4 6 8 7 9 2 1 3
%e A216196 9 1 8 3 4 2 6 7 5
%e A216196 contains 45 diagonals, but also 36 Xoox's, for example the 1 and 5 on rows 1 and 8.
%Y A216196 Cf. A211172.
%K A216196 nonn
%O A216196 1,2
%A A216196 _Jon Perry_, Mar 12 2013