"PIYUSH TABLE AND FORMULA FOR SQUARE"

             N2 =   0   + (20 N1 – 19) N + (2 N – 2) N / 2) N / 2

                              N2² = N² + 20 N N1 – 20N + 0

             N2 = 100 + (20 N1 – 19) N + (2 N – 2) N / 2

                               N2² = N² + 20 N N1 – 20N +100

             N2 = 400 + (20 N1 – 19) N + (2 N – 2) N / 2

                               N2² = N² + 20 N N1 – 20N +400

             N2 = 900 + (20 N1 – 19) N + (2 N – 2) N / 2

                               N2² = N² + 20 N N1 – 20N +900

          WHERE

                   N   = FIRST DIGIT OF WHICH NUMBER,S SQUARE

                   N1 = VALUE GET FROM TABLE

                   N2 = NUMBER OF WHICH YOU SQUARE

FOR EXAMPLE

                   9 = 0 + (20 × 1 – 19) 9 + (2 × 9 – 2)9/2

                      = 0 + 9 + 72

                      = 81

                   11 = 100 + (20 × 2 – 19) + (2 × 1 – 2)1/2

                       = 100 + (40 – 19) + 0

                      = 100 + 21