First numbers that belong to both sets:
11,
88,
111,
888,
1111,
6699,
8888,
9966,
11111,
88888,
110011,
111111,
118811,
660099,
661199,
666999,
668899,
880088,
881188,
888888,
990066,
991166,
998866,
999666,
1100011,
1111111,
1188811,
6600099,
6611199,
6688899,
8800088,
8811188,
8888888,
9900066,
9911166,
9988866,
11000011,
11100111,
11111111,
11188111,
11669911,
11888811,
11996611,
66000099,
66111199,
66600999,
66611999,
66669999,
66688999,
66888899,
66996699,
88000088,
88111188,
88669988,
88800888,
88811888,
88888888,
88996688,
99000066,
99111166,
99669966,
99888866,
99900666,
99911666,
99988666,
99996666,
110000011,
111000111,
111111111,
111888111,
118888811,
660000099,
661111199,
666000999,
666111999,
666888999,
668888899,
880000088,
881111188,
888000888,
888111888,
888888888,
990000066,
991111166,
998888866,
999000666,
999111666,
999888666,
1100000011,
1100110011,
1100880011,
1110000111,
1111001111,
1111111111,
1111881111,
1116699111,
1118888111,
1119966111,
1166009911,
1166119911,
1166699911,
1166889911,
1188008811,
1188118811,
1188888811,
1199006611,
1199116611,
1199886611,
1199966611,
6600000099,
6600110099,
6600880099,
6611001199,
6611111199,
6611881199,
6660000999,
6661111999,
6666009999,
6666119999,
6666699999,
6666889999,
6668888999,
6669966999,
6688008899,
6688118899,
6688888899,
6699006699,
6699116699,
6699886699,
6699966699,
8800000088,
8800110088,
8800880088,
8811001188,
8811111188,
8811881188,
8866009988,
8866119988,
8866699988,
8866889988,
8880000888,
8881111888,
8886699888,
8888008888,
8888118888,
8888888888,
8889966888,
8899006688,
8899116688,
8899886688,
8899966688,
9900000066,
9900110066,
9900880066,
9911001166,
9911111166,
9911881166,
9966009966,
9966119966,
9966699966,
9966889966,
9988008866,
9988118866,
9988888866,
9990000666,
9991111666,
9996699666,
9998888666,
9999006666,
9999116666,
9999886666,
9999966666,
11000000011,
11001110011,
11008880011,
11100000111,
11110001111,
11111111111,
11118881111,
11188888111,
11660009911,
11661119911,
11668889911,
11880008811,
11881118811,
11888888811,
11990006611,
11991116611,
11998886611,
66000000099,
66001110099,
66008880099,
66110001199,
66111111199,
66118881199,
66600000999,
66611111999,
66660009999,
66661119999,
66668889999,
66688888999,
66880008899,
66881118899,
66888888899,
66990006699,
66991116699,
66998886699,
88000000088,
88001110088,
88008880088,
88110001188,
88111111188,
88118881188,
88660009988,
88661119988,
88668889988,
88800000888,
88811111888,
88880008888,
88881118888,
88888888888,
88990006688,
88991116688,
88998886688,
99000000066,
99001110066,
99008880066,
99110001166,
99111111166,
99118881166,
99660009966,
99661119966,
99668889966,
99880008866,
99881118866,
99888888866,
99900000666,
99911111666,
99988888666,
99990006666,
99991116666,
99998886666,
110000000011,
110001100011,
110008800011,
110011110011,
110066990011,
110088880011,
110099660011,
111000000111,
111001100111,
111008800111,
111100001111,
111110011111,
111111111111,
111118811111,
111166991111,
111188881111,
111199661111,
111660099111,
111661199111,
111666999111,
111668899111,
111880088111,
111881188111,
111888888111,
111990066111,
111991166111,
111998866111,
111999666111,
116600009911,
116611119911,
116660099911,
116661199911,
116666999911,
116668899911,
116688889911,
116699669911,
118800008811,
118811118811.
Some larger examples :
999888111888666,
999888888888666,
999900000006666,
999900111006666,
999900888006666,
999911000116666,
999911111116666,
999911888116666,
999966000996666,
999966111996666,
999966888996666,
999988000886666,
999988111886666,
999988888886666,
999990000066666,
999991111166666,
999998888866666,
999999000666666,
999999111666666,
999999888666666.