If a n = 1 {\displaystyle a_{n}=1} for n ≥ 1 {\displaystyle n\geq 1} and ϕ ( x ) = 1 / x , {\displaystyle \phi (x)=1/x,} then A ( x ) = ⌊ x ⌋ {\displaystyle A(x)=\lfloor x\rfloor } and the formula yields