Hey Square...

Decimal

1111111111 square = 1234567900987654321 ... 'Missing' Eight Ms.SideWays

<:3 ... 9L6 ... You lookinG four Me? ;)~

... @8@ ... Indeed;

1 square = 1

11 square = 121
111 square = 12321
1111 square = 1234321
11111 square = 123454321
111111 square = 12345654321
1111111 square = 1234567654321
11111111 square = 123456787654321
111111111 square = 12345678987654321

1111111111 square = 1234567 900987654321