Updated production rules:
rule_4: A2 -> 21 A10 A9
rule_16: A13 -> 27 21 A15 A14
rule_28: A23 -> 3 2 28 1
rule_35: A28 -> 32 A8 A30
rule_37: A30 -> 12 22 30 21
rule_43: A35 -> 11 2 34 1
rule_47: A38 -> 6 2 35 1
rule_50: A40 -> 9 2 36 1