text: Enneadecagonal number | Function to calculate Enneadecagonal number ; Formula for finding nth Enneadecagonal number ; Driver code
code: function nthEnneadecagonal ( n ) { return ( 17 * n * n - 15 * n ) / 2 ; } let n = 6 ; document . write ( n + " " ) ; document . write ( nthEnneadecagonal ( n ) ) ;