0	0
2	3
4	6
6	9
8	12
10	15
12	18
14	21
16	24
18	27
\N	0
\N	-1
\N	-2
\N	0
\N	-1
\N	-2
0	0
2	3
4	6
6	9
8	12
10	15
12	18
14	21
16	24
18	27
12	18
14	21
16	24
18	27
0	0
2	3
4	6
6	9
8	12