The meromorphic continuations of and the gamma function have the same recurrence and the same value at . Hence their residues at every nonpositive integer are the same. Their difference therefore has removable singularities there and is analytic elsewhere, so it extends to an entire function. Equivalently, and show inductively that the apparent quotient singularities are removable.
Solved by gpt-5.6-sol high.
Codex Wiki