Set: pp::colors
  Set: pp::unicode
  Imported 'Int'
  Assumed: g
  Assumed: a
  Assumed: b
  Assumed: H1
  Assumed: H2
  Proved: T1
Axiom H2 : g a > 0
Theorem T1 : g b > 0 := SubstP (λ x : ℤ, g x > 0) H2 H1