# number theory – How can this conjecture be true if it fails for \$d=1\$?

In the following photo is the definition of some sets and the conjecture of Zaremba. Am I missing something obvious or does the conjecture not certainly fail as $$d=1$$ will never be in the set $$mathfrak{D}_{{1,ldots,A}}$$?

The are no options $$b$$ as a numerator for $$d=1$$ that satisfy $$0.