A standard card deck comprises thirteen ranks in four suits. However, modern decks have two additional Jokers, which neither have a suit nor a rank, for a total of cards. If we shuffle such a deck and draw cards without replacement, then we would need, on average, approximately cards so that we have at least one card for each rank.
Now, assume you have such decks, each with a different back design. We shuffle all cards together and draw cards without replacement. What is the expected number of cards needed so every suit, rank and deck design have at least one card?
Give your answer rounded to eight places after the decimal point.
Write-up coming later
The complete problem is available here. An approach, code, and answer will be added later.