First numbers that belong to both sets:
11,
22,
33,
44,
55,
77,
99,
111,
333,
555,
777,
999,
1111,
1133,
1155,
1166,
1177,
1199,
2211,
2222,
2233,
2255,
2266,
2277,
2299,
3311,
3322,
3333,
3355,
3377,
3399,
4411,
4433,
4444,
4455,
4466,
4477,
4499,
5511,
5522,
5533,
5555,
5566,
5577,
5588,
5599,
6611,
6622,
6633,
6644,
6655,
6677,
6699,
7711,
7733,
7755,
7766,
7777,
7799,
8811,
8822,
8833,
8855,
8866,
8877,
8899,
9911,
9922,
9933,
9955,
9977,
9988,
9999,
11111,
11122,
11133,
11155,
11177,
11188,
11199,
11222,
11333,
11444,
11555,
11666,
11777,
11888,
11999,
22111,
22211,
22222,
22233,
22244,
22255,
22277,
22299,
22333,
22444,
22555,
22666,
22777,
22888,
22999,
33111,
33311,
33322,
33333,
33344,
33355,
33377,
33388,
33399,
33555,
33777,
33999,
44111,
44222,
44333,
44411,
44422,
44433,
44444,
44455,
44477,
44488,
44499,
44555,
44666,
44777,
44888,
44999,
55111,
55222,
55333,
55444,
55511,
55522,
55533,
55544,
55555,
55577,
55588,
55599,
55666,
55777,
55999,
66111,
66333,
66555,
66611,
66622,
66633,
66644,
66655,
66677,
66688,
66699,
66777,
66999,
77111,
77222,
77333,
77444,
77555,
77666,
77711,
77722,
77733,
77755,
77777,
77788,
77799,
77888,
77999,
88111,
88222,
88333,
88444,
88555,
88666,
88777,
88811,
88822,
88833,
88855,
88877,
88888,
88899,
88999,
99111,
99333,
99555,
99777,
99911,
99922,
99933,
99955,
99977,
99999,
110011,
110033,
110044,
110055,
110066,
110077,
110099,
111111,
111122,
111133,
111155,
111166,
111177,
111199,
111333,
111555,
111777,
111999,
112211,
112222,
112233,
112244,
112255,
112277,
112299,
113311,
113333,
113355,
113366,
113377,
113399,
114411,
114422,
114433,
114455,
114466,
114477,
114499,
115511,
115522,
115533,
115555,
115577,
115588,
115599,
116611,
116633,
116644,
116666,
116677,
116699,
117711,
117722,
117733,
117755,
117766,
117777,
117788,
117799,
118811,
118822,
118833,
118844,
118855,
118877,
118899,
119911,
119933,
119955,
119977,
119999,
220011,
220022,
220033,
220055,
220066,
220077,
220099,
221111,
221122,
221133.
Some larger examples :
9998811,
9998822,
9998833,
9998855,
9998866,
9998877,
9998888,
9998899,
9999111,
9999333,
9999555,
9999777,
9999911,
9999922,
9999933,
9999944,
9999955,
9999977,
9999988,
9999999.