| i = intfun(i0) ∨ i ∈ mapFun(intfun, ints0), i ∈ mapFun(intfun, ints0) ↔ (∃ j. j ∈ ints0 ∧ intfun(j) = i), ∀ i, intfun. i ∈ mapFun(intfun, ints0) ↔ (∃ j. j ∈ ints0 ∧ intfun(j) = i) ⊦ i = intfun(i0), ∃ j. (j = i0 ∨ j ∈ ints0) ∧ intfun(j) = i |
j ∈ ints0, intfun(j) ∈ mapFun(intfun, ints0), ∀ i, intfun. i ∈ mapFun(intfun, ints0) ↔ (∃ j. j ∈ ints0 ∧ intfun(j) = i) ⊦ intfun(j) = intfun(i0), ∃ j0. j0 ∈ ints0 ∧ intfun(j0) = intfun(j)