Removing spaces between cells using formula

Hi I was wondering if you could help me with something, say that you have three colums, first column contains ten transactions (1,2,3,4,5,6,7,8,9,10) which the user will input, column 2 and 3 will separate the transactions in to two Column 2 (1,2,_,4,5,_,_,8,9,10) and Column 3 (_,_,3_,_,6,7,_,_,_). Now on another column I want to get the transactions from column 2 and display them without spaces using a formula/function (i.e. New Column (1,2,4,5,8,9,10)). How do I do this?