A member who is also a member of the state teachers retirement system or the school employees retirement system shall purchase credit for any service for which the member exempted self under section 145.03 or 3309.23 of the Revised Code, or former section 3307.25 or 3309.25 of the Revised Code, or was exempt under section 3307.24 of the Revised Code, from the retirement system in which the member has the greatest number of years of service credit. If the member receives benefits under section 145.37 of the Revised Code, the system that is the paying system under that section shall receive from the system or systems that are transferring systems the amounts paid by the member for purchase of credit for exempt service plus interest at the actuarial assumption rate of the transferring system. The interest shall be for the period beginning on the date of the member's last payment for purchase of the credit and ending on the date of the member's retirement.
R.C. § 145.28