+{
+ unsigned result = 0;
+ ex e, d;
+
+ e = 1 + x + pow(x, 2) + pow(x, 3);
+ d = Order(1);
+ result += check_series(e, 0, d, 0);
+ d = 1 + Order(x);
+ result += check_series(e, 0, d, 1);
+ d = 1 + x + Order(pow(x, 2));
+ result += check_series(e, 0, d, 2);
+ d = 1 + x + pow(x, 2) + Order(pow(x, 3));
+ result += check_series(e, 0, d, 3);
+ d = 1 + x + pow(x, 2) + pow(x, 3);
+ result += check_series(e, 0, d, 4);
+ return result;
+}
+
+// Series of special functions
+static unsigned series5(void)