[Diphenyl Oxalate]

pentagrant,

<script>
function Determinant(A)
{  
    var n = A.length, subA = [], detA = 0;
        
    if (n==1) return A[0][0];
    if (n==2) return (A[0][0]*A[1][1]-A[0][1]*A[1][0]);
    if (n==3)
       { return ((A[0][0]*A[1][1]*A[2][2]+A[0][1]*A[1][2]*A[2][0]+A[0][2]*A[1][0]*A[2][1])
                 -(A[0][0]*A[1][2]*A[2][1]+A[0][1]*A[1][0]*A[2][2]+A[0][2]*A[1][1]*A[2][0]));
       }

    for (var i=0; i<n; i++)
        { for (var h=0; h<n-1; h++) subA[h]=[];
          for (var a=1; a<n; a++)
              { for (var b=0; b<n; b++)
                    { if (b<i)       subA[a-1][ b ] = A[ a ][ b ];
                      else if (b>i)  subA[a-1][b-1] = A[ a ][ b ];
                    }
              }
          var sign = (i%2==0) ? 1 : -1;
          detA += sign * A[0][i] * Determinant(subA);
        }

    return detA;
}

function generate()
{
	var rowCount = document.getElementById('rowCount').value;
	var colCount = document.getElementById('colCount').value;
	var tbl = document.createElement('table');
	tbl.insertRow(-1);
	for (var j=0; j<=colCount; j++)	tbl.tBodies[0].rows[0].insertCell(-1).innerHTML = j||' ';
	for (var i=1; i<=rowCount; i++)
	{
		tbl.insertRow(-1).insertCell(-1).innerHTML = i;
		for (var j=1; j<=colCount; j++)	
		{
			var input = document.createElement('input');
			input.id=input.name='m_'+i+'_'+j;
			input.size = "5";
			tbl.tBodies[0].rows[i].insertCell(-1).appendChild(input);
		}
	}
	document.body.appendChild(tbl);
	var det = document.createElement("INPUT");
	document.body.insertBefore(det, tbl);
	det.type = "button";
	det.value = "Determinant";
	det.onclick = function () {
		var mtx = [];
		for (var i = 1; i <= rowCount; i++) {
			mtx[i - 1] = [];
			for (var j = 1; j <= colCount; j++)
				mtx[i - 1].push( tbl.rows[i].cells[j].getElementsByTagName("input")[0].value );
		}
		alert( Determinant( mtx ) );
	};
}
</script>
rowCount: <input id='rowCount' type='text' value='4' /><br />
colCount: <input id='colCount' type='text' value='5' /><br />
<button onclick="generate()">generate</button>