T:Type, m, n:, f:({m..n}T). n<m  ||f{m..n}|| = n-m 

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Definitions	P & Q, i  j < k, S  T, S  T, True, i<j, b, b, , ij, T, P  Q, P  Q, Unit, {...i}, {T}, x. t(x), f{m..n}, ||as||, {i..j}, x:A. B(x), Prop, P  Q, False, A, AB, P  Q, Dec(P), t  T
Lemmas	int seg wf, decidable le, length wf1, listify wf, int lower ind, int lower 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, bnot wf, assert wf, lt int wf, le wf