I don't understand the downvotes on my question here: Make $2$ cubes out of $1729$ unit cubes, expected number of times you have to paint
I had shown my work so far, and was not asking for a complete solution but just some help with getting unstuck. Furthermore, this is not a homework question, as it's a question from a math competition from over a decade ago. So I'm not sure why as of now there are 6 downvotes without explanation... does anybody know? It's fine to downvote and then give a reason in the comments, which would help me with asking better questions in the future, but 6 people downvoted as if the reason for doing so was self-evident.