Updated production rules:
rule_18: A14 -> 17 22 20 21
rule_25: A21 -> 7 22 27 21
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