13. As shown in the figure, a large square is divided into six smaller squares. If two small squares share more than one common point, they are called adjacent. Fill in the numbers $1, 2, 3, 4, 5, 6$ into the figure, with one number in each small square, such that the difference between the numbers in adjacent squares is never 3. The number of different ways to do this is $\qquad$ kinds.
【Analysis】Start by filling in the most adjacent $\mathrm{F}$, and find that 1 to 6 can all be filled, giving 6 possibilities. Let's assume 1 is filled in, at which point we find that the difference between $\mathrm{ABDE}$ and 1 cannot be 3, so $\mathrm{ABDE}$ must be one of $2, 3, 5, 6$; at this point, we find that $\mathrm{C}$ is determined to be 4, with one way to fill it. $\mathrm{A}$ can have 4 possibilities (2, 3, 5, 6, any one of them), let's assume $\mathrm{A}$ is filled with 2, $\mathrm{B}$ has 2 ways to fill, $\mathrm{D}, \mathrm{E}$ have 2 ways to fill: $6 \times 4 \times 2 \times 2=96$ (ways).