How can I simplify this formula and also create a loop?

This is a simple If formula:   =IF(G26=1,8,IF(G26=2,16,IF(G26=3,24,IF(G26=4,32,IF(G26=5,40,IF(G26=6,48,IF(G26=7,56,IF(G26=8,64,IF(G26=9,72,IF(G26=10,80))))))))))   cell G26 is an input cell where...