1*8+1=9
12*8+2=98
123*8+3=987
1234*8+4=9876
12345*8+5=98765
123456*8+6=987654
1234567*8+7=9876543
12345678*8+8=98765432
123456789*8+9=987654321.
1*9+2=11
12*9+3=111
123*9+4=1111
1234*9+5=11111
12345*9+6=111111
123456*9+7=1111111
1234567*9+8=11111111
12345678*9+9=111111111
123456789*9+10=1111111111 신기하고 재미있지 않아요?