(* SN POINTWISE EXTENSION OF A CONTEXT-SENSITIVE REALTION FOR TERMS *********)
-(* alternative definition of lpx_sn *)
+(* Note: alternative definition of lpx_sn *)
definition lpx_sn_alt: relation3 lenv term term → relation lenv ≝
λR,L1,L2. |L1| = |L2| ∧
(∀I1,I2,K1,K2,V1,V2,i.