First numbers that belong to both sets:
12,
23,
34,
45,
56,
67,
78,
89,
123,
234,
345,
456,
567,
678,
789,
1234,
2345,
3456,
4567,
5678,
6789,
12345,
23456,
34567,
45678,
56789,
123456,
234567,
345678,
456789,
1234567,
2345678,
3456789,
12345678,
23456789,
123456789.