Chen　et　al.　(Phys　RevA73:　012303,　2006)　constructed　this　＂starlike　cluster＂　state,　which　involves　one　qubit　located　at　the　center　and　n　neighboring　two-qubit　arms.　This　genuine　entangled　state　has　been　used　for　the　construction　of　2D　and　3D　cluster　states,　topological　one-way　computation,　and　dynamical　quantum　secret　sharing.　In　this　paper,　we　investigate　the　usefulness　of　this　starlike　cluster　state　and　propose　a　theoretically　extensible　quantum　digital　signature　scheme.　The　proposed　scheme　can　be　theoretically　generalized　to　more　than　three　participants.　Moreover,　it　retains　the　merits　of　no　requirements　such　as　authenticated　quantum　channels　and　long-term　quantum　memory.　We　also　give　a　security　proof　for　the　proposed　scheme　against　repudiation　and　forgery.