i:, x, l:Top. (x.l)[i+1] ~ l[i] 

latex

Definitions	t  T, , nth_tl(n;as), Prop, True, x:A. B(x), b, b, i<j, , AB, ij, P  Q, T, P  Q, P & Q, P  Q, Unit, tl(l), l[i], Top
Lemmas	top wf, nat wf, eqtt to assert, assert of le int, iff transitivity, eqff to assert, squash wf, true wf, bnot of le int, assert of lt int, le int wf, bool wf, le wf, lt int wf, assert wf, bnot wf