Merge cells in R dataframe and download the result as an excel sheet

Question

I have the following dataframe in R 


Sample=data.frame(\'A_P1_P2_2013_X_F\'=c(1,2,20,50,90,200,NA), 
\'A_P1_P2_2013_X_A\'=c(1,2,20,50,90,NA,NA), \'A_P1_P2_2013_Y_F\'=c