lean2/tests/lean/run/refl_beta.lean

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Text

import data.stream
open nat
namespace stream
variable A : Type
set_option pp.beta false
theorem mem_of_mem_odd₂ (a : A) (s : stream A) : a ∈ odd s → a ∈ s :=
assume ainos, obtain n (h : a = nth n (odd s)), from ainos,
exists.intro (2*n+1) (by rewrite [h, nth_odd])
end stream