Driver Code
public static void main ( String [ ] args ) { int n = 3 ; System . out . print ( n + " th ▁ centered ▁ " + " octadecagonal ▁ number ▁ : ▁ " ) ; System . out . println ( center_octadecagon_num ( n ) ) ; n = 13 ; System . out . print ( n + " th ▁ centered ▁ " + " octadecagonal ▁ number ▁ : ▁ " ) ; System . out . println ( center_octadecagon_num ( n ) ) ; } }