In[]:=
Clear["Global`*"]EQ=1/4Subsuperscript[n,1,4]+1/2Subsuperscript[n,2,2]Subsuperscript[n,1,2]+1/4Subsuperscript[n,2,4]Simplify[EQ]FullSimplify[EQ]Quit[]
Out[]=
4
n
1
4
1
2
2
n
1
2
n
2
4
n
2
4
Out[]=
1
4
4
n
1
2
n
1
2
n
2
4
n
2
Out[]=
1
4
4
n
1
2
n
1
2
n
2
4
n
2