We can calculate the expected number of times GDB-13 needs to be sampled to obtain 100% of the database. This problem is commonly known in mathematics as the "coupon collector problem" . It was originally used to calculate the number of coupons (or stickers) that are needed to be bought to be able to obtain the full collection, knowing that every time a coupon is bought it is sampled with replacement from a distribution containing all possible coupons. Formally, for a uniform distribution with 𝑛 coupons: