Question 686415
A reminder that the definition of logarithms is the logarithmic function with base {{{b}}}, where{{{ b > 0}}} and {{{b <>0}}}, and is defined as {{{log(b,x)=y}}} if and only if {{{b^y=x}}}. 

in your case {{{4^7= 16384 }}} means {{{b=4}}}, {{{y=7}}}, and {{{x=16384}}}; so,in logarithmic form it will be: 

{{{log(4,16384)=7}}}