Driver Code
static public void Main ( ) { int n = 4 ; Console . Write ( n + " th ▁ Icosidigonal ▁ " + " number ▁ : " ) ; Console . WriteLine ( icosidigonal_num ( n ) ) ; n = 8 ; Console . Write ( n + " th ▁ Icosidigonal ▁ " + " number ▁ : " ) ; Console . WriteLine ( icosidigonal_num ( n ) ) ; } }