Updated production rules:
rule_2: A2 -> A13 A3 A14 9
rule_13: A7 -> 21 1
rule_17: A8 -> 4 2
rule_27: A13 -> 8 A7
rule_28: A14 -> 15 A7
rule_31: A16 -> 16 1
rule_46: A22 -> 25 6 A23 5 26
rule_58: A28 -> 13 A22
rule_65: A32 -> 12 A22
rule_70: A35 -> A22 14 1
rule_74: A37 -> 7 A7
rule_84: A43 -> 17 A7 5 19
rule_86: A45 -> 2 1