find the Ist term of the the series who's 2nd and subsiquent term are 8,3,0,-1,0

x              f(x)               ∆ f(x)             ∆²f(x)

2                8

                                       -5

3                3                                           2

                                       -3

4                0                                           2

                                       -1

5              -1                                            2

                                       -1

6                0

F(1) = E^-1  f(2)

        = (1 + ∆)^-1 f(2)

        = (1 - ∆ + ∆²)  f(2)

     = f(2) - ∆ f(2) + ∆² f(2)

      = 8 – (-5) + 2

      =15

F(2) = E^-1 f(3)

        = (1 +∆)^-1 f(3)

        = (1 - ∆ + ∆²) f(3)

       

        = f(3) - ∆f(3) + ∆² f(3)

        = 3 – (-3) + 2

        = 3 + 3 + 2

F(2) = 8