look at the pattern and Solve
1 = 1X1
121 =__x__
12321 =__x__
1234321=__x__
_____ =11111x11111
It can be observed that the squares of the given numbers can be found by first writing the counting number up to the number of 1's and then writing the reverse counting till 1.
Thus,
1×1=1
11×11=121
111×111=12321
1111×1111=1234321
11111×11111=123454321