Question 550461
guess n check works...lol took me 1 min 
{{{3^2+3=12}}}
{{{12^2+3=147}}}
{{{147^2+3=21612}}}

i started with 3*4=12
but 12*4=48 not 147
12^2=144 and 147-144=3
so that pattern is {{{x^2+3=y}}}and {{{y^2+3=z}}}
i tried 3^2+3=12 then 12^2+3=147 so naturally its 147^2+3