In[]:=
InverseFourierSequenceTransform[2πDiracDelta[ω-ω0],ω,n]
Out[]=
nω0

In[]:=
InverseFourierSequenceTransform[2πDiracComb[ω-ω0],ω,n]
Out[]=
2πInverseFourierSequenceTransform[DiracComb[ω-ω0],ω,n]
In[]:=
FourierSequenceTransform[Exp[I*n],n,ω]
Out[]=
DiracComb
-1+ω
2π

In[]:=
FourierSequenceTransform[Exp[I*n*r],n,ω]
Out[]=
FourierSequenceTransform
nr

,n,ω