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Indeed! Here is Sudoku, formulated as a SAT problem. You can use for example SICStus Prolog to run it:

    sudoku(Rows) :-
            length(Rows, 9), maplist(same_length(Rows), Rows),
            maplist(row_booleans, Rows, BRows),
            maplist(booleans_distinct, BRows),
            transpose(BRows, BColumns),
            maplist(booleans_distinct, BColumns),
            BRows = [As,Bs,Cs,Ds,Es,Fs,Gs,Hs,Is],
            blocks(As, Bs, Cs), blocks(Ds, Es, Fs), blocks(Gs, Hs, Is).

    blocks([], [], []).
    blocks([N1,N2,N3|Ns1], [N4,N5,N6|Ns2], [N7,N8,N9|Ns3]) :-
            booleans_distinct([N1,N2,N3,N4,N5,N6,N7,N8,N9]),
            blocks(Ns1, Ns2, Ns3).

    booleans_distinct(Bs) :-
            transpose(Bs, Ts),
            maplist(card1, Ts).

    card1(Bs) :- sat(card([1],Bs)).

    row_booleans(Row, Bs) :-
            same_length(Row, Bs),
            maplist(cell_boolean, Row, Bs).

    cell_boolean(Num, Bs) :-
            length(Bs, 9),
            sat(card([1],Bs)),
            element(Num, Bs, 1).
This uses the sat/1 constraint to denote Boolean satisfiability.

Here is an example Soduku problem, taken from Donald Knuth's The Art of Computer Programming:

    knuth(b, [[1,_,3,_,5,6,_,8,9],
              [5,9,7,3,8,_,6,1,_],
              [6,8,_,1,_,9,3,_,5],
              [9,5,6,_,3,1,8,_,7],
              [_,3,1,5,_,8,9,6,_],
              [2,_,8,9,6,_,1,5,3],
              [8,_,9,6,_,5,_,3,1],
              [_,6,5,_,1,3,2,9,8],
              [3,1,_,8,9,_,5,_,6]]).
Sample query and result:

    ?- knuth(b, Rows),
       sudoku(Rows),
       maplist(portray_clause, Rows).
    [1, 2, 3, 4, 5, 6, 7, 8, 9].
    [5, 9, 7, 3, 8, 2, 6, 1, 4].
    [6, 8, 4, 1, 7, 9, 3, 2, 5].
    [9, 5, 6, 2, 3, 1, 8, 4, 7].
    [7, 3, 1, 5, 4, 8, 9, 6, 2].
    [2, 4, 8, 9, 6, 7, 1, 5, 3].
    [8, 7, 9, 6, 2, 5, 4, 3, 1].
    [4, 6, 5, 7, 1, 3, 2, 9, 8].
    [3, 1, 2, 8, 9, 4, 5, 7, 6].


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