ProofNum.k9: law of lawful-fields@0.1.1.0
Import: import lawful-fields@0.1.1.0/proof_num.bend as ProofNum
Lines 214-217 of lawful-fields@0.1.1.0/proof_num.bend: https://jend.leeeet.dev/read.txt?path=lawful-fields@0.1.1.0/proof_num.bend&start_line=214&end_line=217

import Base

law k9:
  for +x: U32
  for +hle: {U32.is_le(x, 57) == True{} : Bool}
  {Nat.is_le(Nat.sub(U32.to_nat(x), 48n), 9n) == True{} : Bool}

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.trans
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_le
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.sub
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_le
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.to_nat
  https://jend.leeeet.dev/definition.txt?path=lawful-fields@0.1.1.0/proof_num.bend&name=sub_mono
  https://jend.leeeet.dev/definition.txt?path=lawful-words@0.1.0.0/proof_u32.bend&name=is_le_to_nat