User blog comment:DrCocktor/Figure out the rule of this function/@comment-35470197-20190411230056/@comment-35470197-20190412224357

Just kind of a joke :D Sorry if inappropriate. Well, I reminded a similar quiz.

Q: "What is the rule of the sequence a_0 = 1, a_1 = 3, a_2 = 11, a_3 = 17, a_4 = 21, a_5 = 35, a_6 = 41, ...?" A: "It is a sequece of numbers."

Also, as CatIsFluffy guessed, I actually reminded PsiCubed2's blog post.