Nuprl Lemma : firstn_append_front_singleton

∀[L:Top List]. ∀a:Top. (firstn(||L @ [a]|| - 1;L @ [a]) ~ L)


Proof




Definitions occuring in Statement :  firstn: firstn(n;as),  length: ||as||,  append: as @ bs,  cons: [a / b],  nil: [],  list: T List,  uall: ∀[x:A]. B[x],  top: Top,  all: ∀x:A. B[x],  subtract: n - m,  natural_number: $n,  sqequal: s ~ t
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x]
Lemmas referenced :  length-singleton,  firstn_append_front,  cons_wf,  top_wf,  nil_wf,  list_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lambdaFormation,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  dependent_functionElimination,  sqequalRule,  lambdaEquality,  sqequalAxiom,  because_Cache

Latex:
\mforall{}[L:Top  List].  \mforall{}a:Top.  (firstn(||L  @  [a]||  -  1;L  @  [a])  \msim{}  L)



Date html generated: 2016_05_14-PM-02_08_31
Last ObjectModification: 2015_12_26-PM-05_06_46

Theory : list_1


Home Index