A Short Proof of the Grigorchuk-Cohen Cogrowth Theorem
A Short Proof of the Grigorchuk-Cohen Cogrowth Theorem
Let G be a group generated by g\,...,gr ■ There are exactly 2r(2r -l)"_l reduced words in g\,...,gr of length n .Part of them, say y" represents identity element of G .Let y = lim sup y" .We give a short proof of the theorem of Grigorchuk and Cohen which …