No.

Three closest points

Determinants

Inside or outside the triangle

Recommend

or not

15

13, 16, 10

;

;

Outside

No

11

13, 9, 14

;

;

Inside

Yes

5

3, 8, 10

;

;

Outside

No

8

10, 6, 11

;

;

Inside

Yes

17*

7, 2, 4,

;

;

Outside

No

18*

13, 11, 8

;

;

Inside

Yes