`A = 1``1/2019 xx 1``1/2018 xx 1``1/2017xx......xx1``1/2`
`A=2020/2019 xx 2019 xx 2018 xx .... xx 3/2`
`A = ( 2020xx2019xx20218xx.....xx3)/(2019xx2018xx2017xx...xx2)`
`A = ( 2020 xx ( 2019xx20218xx.....xx3))/( 2 xx ( 2019xx2018xx2017xx...xx3))`
`A = 2020/2`
`A=1010`