Question

Observe the following pattern and supply the missing number.
${11}^2=121$
${101}^2=10201$
${10101}^2=102030201$
${1010101}^2=................$
$.............{.}^2=10203040504030201$

Answer 1

${1010101}^2=1020304030201$
${101010101}^2=10203040504030201$
Start with $1$ followed by a zero and go up to as many number as there are number of $1s$ given, follow the same pattern in reverse order.