cp's OEIS Frontend

A172478 The number of ways to dissect an n X n square into polyominoes of size n and then fill it to make it a Latin square, with the extra requirement that each number occurs within each polyomino exactly once.

%I A172478 #9 Dec 16 2016 03:11:53
%S A172478 1,4,72,13872,11762160,234312972480,41182101508222080
%N A172478 The number of ways to dissect an n X n square into polyominoes of size n and then fill it to make it a Latin square, with the extra requirement that each number occurs within each polyomino exactly once.
%C A172478 a(n) is the number of completed n X n jigsaw sudoku puzzles.
%D A172478 J. de Ruiter, On Jigsaw Sudoku Puzzles and Related Topics, Bachelor Thesis, Leiden Institute of Advanced Computer Science, 2010. [From _Johan de Ruiter_, Jun 15 2010]
%e A172478 A 2 X 2 square can be covered by two dominoes by either positioning them vertically or horizontally. Both of these coverings allow for two 2 X 2 Latin squares without violating the extra constraint.
%Y A172478 Cf. A002860 (Number of Latin squares of order n), A172477 (Number of ways to dissect an n X n square into polyominoes of size n).
%K A172478 nonn
%O A172478 1,2
%A A172478 _Johan de Ruiter_, Feb 04 2010