\(1=\dfrac{1\cdot2}{2}\)

\(3=\dfrac{2\cdot3}{2}\)

\(6=\dfrac{3\cdot4}{2}\)

...............

=> \(2016^{th}=\dfrac{2016\cdot2017}{2}=2033136\)

We have :

1 = \(\dfrac{1.2}{2}\)                            3 = \(\dfrac{2.3}{2}\)                        6 = \(\dfrac{3.4}{2}\)

.............................

2016th = \(\dfrac{2016.2017}{2}\) = 2033136

1=1⋅22

3=2⋅32

6=3⋅42

...............

=> 2016th=2016⋅20172=2033136