We prove $L_{infty}$-formality for the higher cyclic Hochschild complex $chH$ over free associative algebra or path algebra of a quiver. The $chH$ complex is introduced as an appropriate tool for the definition of pre-Calabi-Yau structure. We show that cohomologies of this complex are pure in case of free algebras (path algebras), concentrated in degree zero. It serves as a main ingredient for the formality proof. For any smooth algebra we choose a small qiso subcomplex in the higher cyclic Hochschild complex, which gives rise to a calculus of highly noncommutative monomials, we call them $xidelta$-monomials. The Lie structure on this subcomplex is combinatorially described in terms of $xidelta$-monomials. This subcomplex and a basis of $xidelta$-monomials in combination with arguments from Groebner bases theory serves for the cohomology calculations of the higher cyclic Hochschild complex. The language of $xidelta$-monomials in particular allows an interpretation of pre-Calabi-Yau structure as a noncommutative Poisson structure.
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