How to calculate a complicated permutation?

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I'm writing a play that features a lot of randomization, which will mean that it is different every time, and I'm trying to calculate the number of performance possibilities.

  • It features a number of scenes, which will be performed in a different order each performance.
  • The roles within each scene are to be played by different actors each time.
  • The cast size is also variable!

So there are X amount of scenes, Y amount of roles within the scenes, and Z amount of actors to be filled in each role. (For example: 38 scenes, with 77 total speaking roles to be divided among 9 actors.) The speaking roles would ideally be evenly distributed among the actors.

How would I calculate the number of performance possibilities this play can hold?

Hopefully I'm making myself clear! Thanks for any help you can offer!

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With this data

$38$ scenes, with $77$ total speaking roles to be divided among $9$ actors

there are $38! = 5.23 \times 10^{44}$ orders for the scenes, even before assigning actors. That's more than $5$ followed by 44 $0$'s.

For convenience estimating, I'll work with $72$ rather than $77$ roles, since that's a multiple of $9$ - each actor will get $8$ roles. There are $72!/(8!)^9 \approx 2.2 \times 10^{62}$ ways to assign the roles.

When you multiply those together you get a number with more than $109$ digits. A googol has a mere $100$ zeroes. This is about a billion googol.