problem([]==>a:u(1)=>b:u(1)=>c:u(1)=>d:u(1)=> ((b=>a)# (d=>b)=>c=>d)=> ((c=>d)=>b)=>a,
repeat dequantify_once,lambda(a,lambda(b,lambda(c,lambda(d,_8985)))),
[problem([a:u(1),b:u(1),c:u(1),d:u(1)]==> ((b=>a)# (d=>b)=>c=>d)=> ((c=>d)=>b)=>a,
 propositional,lambda(v0,lambda(v1,su(spread(v0,[v3,v4,su(v6,[v3 of v2],[v6])]),[v1 of lambda(v2,su(spread(v0,[v4,v5,su(su(su(v9,[v8 of v2],[v9]),[v5 of lambda(v8,v3)],[v8]),[v4 of v3],[v7])]),[v1 of spread(v0,[v3,v4,lambda(v6,su(su(su(su(v10,[v9 of v2],[v10]),[v4 of lambda(v9,v8)],[v9]),[v1 of su(v8,[v4 of lambda(v8,su(v9,[v1 of lambda(v9,v8)],[v9]))],[v8])],[v8]),[v3 of su(su(v8,[v1 of v7],[v8]),[v4 of lambda(v7,su(v8,[v1 of lambda(v8,v7)],[v8]))],[v7])],[v7]))])],[v3]))],[v2]))),
 [
 ]) ext _8985
]).
