Theoretical Foundations of Applied Discrete Mathematics
An extension of Gluskin–Hoszu's and Malyshev's theorems to strong dependent $n$-ary operations
A. V. Cheremushkin Research Institute "Kvant", Moscow
Abstract:
The report presents an extension of Malyshev theorem for
$n$-ary quasigroups with a right or left weak inverse property to the case of strong dependent
$n$-ary operations on a finite set. The main result is the following theorem. Let
$n\ge3$ and a strong dependent
$n$-ary function
$f$ on a finite set
$X$ be such that $f(x_1,\dots,x_n)=g_1(\bar x,h(\bar y,\bar z))=g_2(h(\bar x,\bar y),\bar z)$, for all $(x_1,\dots,x_n)=(\bar x,\bar y,\bar z)\in X^i\times X^{n-i}\times X^i$ and some
$g_1,g_2,h$. Then there exist a permutation
$\sigma$, a monoid "
$\ast$"on
$X$ and an automorphism
$\theta$ of "
$\ast$" such that
$$
\sigma(f(x_1,\dots,x_n))=x_1\ast\theta(x_2)\ast\theta^2(x_3)\ast\dots\ast\theta^{n-1}(x_n),
$$
for all
$x_i\in X$,
$i=1,\dots,n$. As a corollary, the following new proof of Gluskin–Hosszú theorem for strong dependent
$n$-ary semigroups is obtained: if a strong dependent
$n$-ary operation
$[x_1,\dots,x_n]$ admits an identity $[[x_1,\dots,x_n],x_{n+1},\dots,x_{2n-1}]=[x_1,[x_2,\dots,x_{n+1}],x_{n+2},\dots,x_{2n-1}]$, then there exist a monoid "
$\ast$" on
$X$ and an automorphism
$\theta$ of "
$\ast$" such that
$\theta^{n-1}(x)=a\ast x\ast a^{-1}$,
$a\in X$,
$\theta(a)=a$, and $[x_1,\dots,x_n]=x_1\ast\theta(x_2)\ast\theta^2(x_3)\ast\dots\ast\theta^{n-2}(x_{n-1})\ast a\ast x_n$ for all
$x_i\in X$,
$i=1,\dots,n$.
Keywords:
$n$-ary group, $n$-ary semigroup, strong dependent operation, weak invertible operation.
UDC:
519.719.1
DOI:
10.17223/2226308X/11/7