2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/52551A new recursion formula is presented for the correlation functions of the integrable spin 1/2 XXX chain with inhomogeneity. It relates the correlators involving n consecutive lattice sites to those with n-1 and n-2 sites. In a series of papers by V. Korepin and two of the present authors, it was discovered that the correlators have a certain specific structure as functions of the inhomogeneity parameters. Our formula allows for a direct proof of this structure, as well as an exact description of the rational functions which has been left undetermined in the previous works.37 pages, 1 figure, Proof of Lemma 4.8 modifiedHigh Energy Physics - TheoryStatistical MechanicsMathematical PhysicsQuantum Algebratext