Let L $=\{$s$,$ m$,$ G$,$ o$\}$ where s is a unary function symbol, m is a binary function

symbol, G is a binary relation symbol, and o is a constant symbol. Let A be

the model of L with domain A $=$ Z$,$ sA the successor function $($ sA$($a$)=$ a $+1),$

mA multiplication on the integers $($mA$($a$,$ b$)=$ a $$ b$),$ GA the greater$-$than relation

$($GA$($a$,$ b$)$ iff a $>$ b$)$ and oA equal $0($oA $=0).$