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Mathematical arrangement and combination problems
1. Determine the color of point E first. If there are four kinds of C (1 4), then points A and D can only be filled from the remaining three colors, and there are six kinds of A (2 2,3);

2. When the color of E has been determined, you can only choose the color of point F from the remaining three colors.

(1) If F and D are different colors, that is, the color of F is A( 1, 3)=3, and the color of B is A( 1, 2)=2. Please note that C is different from B, F and D at this time, so there is only one color left.

At this time, the filling and coating scheme is: C (1, 4) × A (1, 3) × A (1, 2) =144;

(2) If F and D are of the same color, then F does not need to be selected. At this time, the method of B is A( 1, 2). Considering that C is different from B, F and D at this time (these three points * * * use two colors at this time), then choose C( 1, 2).

At this time, the coating scheme is: c (1, 4 )× a (2,3 )× c (1,2) × a (1, 2) = 96.

The total filling scheme is: 144+96 = 240 kinds.