A calendar is a rectangular sheet of grid paper. We say a calendar complies with the regulations if and only if it satisfies the following three conditions:
(1) Every cell of the calendar is colored white or red, and there are exactly red cells.
(2) If a horizontal row of the calendar has a total of cells, then when we fill in in order starting from the cell in the uppermost-left corner, going from left to right and then from top to bottom, we will not be able to find consecutive numbers whose cells are all white.
(3) If a vertical column of the calendar has a total of cells, then when we fill in in order starting from the cell in the lowermost-left corner, going from bottom to top and then from left to right, we will not be able to find consecutive numbers whose cells are all white (that is to say, if we rotate the whole calendar degrees clockwise, it still satisfies condition (2)).
試問有多少種符合法規的月曆? How many calendars comply with the regulations?
A calendar is a rectangular sheet of grid paper. We say a calendar complies with the regulations if and only if it satisfies the following three conditions:
(1) Every cell of the calendar is colored white or red, and there are exactly red cells.
(2) If a horizontal row of the calendar has a total of cells, then when we fill in in order starting from the cell in the uppermost-left corner, going from left to right and then from top to bottom, we will not be able to find consecutive numbers whose cells are all white.
(3) If a vertical column of the calendar has a total of cells, then when we fill in in order starting from the cell in the lowermost-left corner, going from bottom to top and then from left to right, we will not be able to find consecutive numbers whose cells are all white (that is to say, if we rotate the whole calendar clockwise, it still satisfies condition (2)).
How many calendars comply with the regulations?
