+606 A standard six-sided die is rolled $8$ times. You are told that among the rolls, there was two $1$'s, two $2$'s, two $3$'s, and two $4$s. How many possible sequences of rolls could there have been? (For example, $2,$ $1,$ $3,$ $4,$ $2,$ $1$, $3$, $4$ is one possible sequence.)
