thats where he copied the calculation from:
USE [SRO_VT_ACCOUNT]
GO
/****** Object: UserDefinedFunction [dbo].[make_ip] Script Date: 2015-01-13 00:26:12 ******/
SET ANSI_NULLS OFF
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER function [dbo].[make_ip] (@ip1 bigint, @ip2 bigint, @ip3 bigint, @ip4...