Sorry, this Javascript puzzle doesn't seem to work in your web
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typed arrays).
These puzzles have been successfully run in Firefox 19, Chrome 26,
Internet Explorer 10 and Safari 6.
Fill in the grid with numbers from 1 to the grid size, so that every
number appears exactly once in each row and column, and so that all
the < signs represent true inequalities (i.e. the
number at the pointed end is smaller than the number at the open end).
To place a number, click in a square to select it, then type the
number on the keyboard. To erase a number, click to select a square
and then press Backspace.
Right-click in a square and then type a number to add or remove the
number as a pencil mark, indicating numbers that you think
might go in that square.