free a: bitstring.
free c,d,e:channel.
fun hash(bitstring):bitstring.

equivalence
   (let x = hash(a) in
       out(c, x) | out(d, x)) | out(e, hash(a))

   out(c, hash(a)) | let x = hash(a) in
       (out(d, x) | out(e, x))
 

(* EXPECTPV
RESULT Observational equivalence is true.
0.012s (user 0.012s + system 0.000s), max rss 8676K
END *)
