(Subscript[S, 1]) // FullForm

(Subscript[S, 1,0,1]) // FullForm

f[n_]:=f[n-1]+...

g[ns__] := {ns}

g[1,2,3]

sum[xs__] := Plus[xs]

sum[2,3,4]

sum[]

num[xs___] := Plus[xs]

num[10,12,1,3]

num[]

(Subscript[TS, as__]) := Plus[as]

(Subscript[TS, 0,0,1,1,0])

(Subscript[S, 1,0,1])[K]

(Subscript[S, 1,0,1])[Xp[2,6,3,5] Xp[4,2,5,1] Xp[6,4,1,3]]