User blog comment:DrCeasium/new hyperfactorial array notation/@comment-5150073-20130415141127/@comment-5150073-20130415155554

When 3^3^3^3 on the left to the & operator, it can't be simplified down to 3^762559749487 by the same reason that 3*2 & 3 = {3,3,3 (1) 3,3,3} can't be 6 & 3 = {3,3,3,3,3,3}.