On identities and their generalizations in polyadic groupoids of special form. I

The article focuses on identities and their generalizations in polyadic groupoids of special form, i. e. in polyadic groupoids with $l$-ary operation $\eta_{s,\sigma,k}$, that is called polyadic operation of special form and is defined on Cartesian power $A^k$ of $n$-ary groupoid $<A,\eta>$ by substitution $\sigma\in\mathbf{S}_k$ and $n$-ary operation $\eta$.