The divergence is local in the induced boundary metric and is cancelled by the leading holographic renormalization counterterm
On the regulated cylinder this is
which cancels the divergence of . An overall sign changes if one uses the oppositely signed Euclidean generating functional; the local counterterm changes with it.
When varies, the radial wave equation recursively generates local derivative terms before the normalizable response. Substituting
into
gives
Because the boundary dimension is odd, no logarithmic term is required. Holographic renormalization subtracts these source-dependent pieces, leaving
in the normalization . Equivalently,