Is there partial order over $\{1,2,3,4\}$ such that there're two maximal elements and one least element?

1.2k Views Asked by At

Let set $A=\{1,2,3,4\}$. Is there such a partial order relation over $A$ such that there're two maximal elements and one least element?

I think we could define a partial order as follows: $$ xRy \iff x>y \quad \land \quad\text{x and y are prime} $$ Thus for $A$ we have $\{(3,1), (4,1)\}$. There're no other elements less than $1$ so it's the least element. And this way $3$ and $4$ are maximal elements.

Not sure if this is correct.

1

There are 1 best solutions below

0
On BEST ANSWER

Y

(the partially ordered set whose poset diagram looks like the alphabet Y, where we assume the order is increasing from bottom to top. see below image for more details).

enter image description here