Nuprl Lemma : combinations-choose
∀[m,n:ℕ].  C(m;n) = (choose(n;m) * (m)!) ∈ ℤ supposing m ≤ n
Proof
Definitions occuring in Statement : 
combinations: C(n;m)
, 
fact: (n)!
, 
nat: ℕ
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
le: A ≤ B
, 
multiply: n * m
, 
int: ℤ
, 
equal: s = t ∈ T
, 
choose: choose(n;i)
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
and: P ∧ Q
, 
uimplies: b supposing a
, 
nat: ℕ
, 
not: ¬A
, 
implies: P 
⇒ Q
, 
false: False
, 
all: ∀x:A. B[x]
, 
or: P ∨ Q
, 
sq_type: SQType(T)
, 
guard: {T}
, 
uiff: uiff(P;Q)
, 
ifthenelse: if b then t else f fi 
, 
btrue: tt
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
bfalse: ff
, 
int_iseg: {i...j}
, 
cand: A c∧ B
, 
ge: i ≥ j 
, 
decidable: Dec(P)
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
exists: ∃x:A. B[x]
, 
top: Top
, 
prop: ℙ
, 
subtype_rel: A ⊆r B
, 
nat_plus: ℕ+
Lemmas referenced : 
combinations-formula, 
istype-le, 
istype-nat, 
le_int_wf, 
assert_wf, 
bnot_wf, 
not_wf, 
le_wf, 
istype-assert, 
istype-void, 
bool_cases, 
subtype_base_sq, 
bool_wf, 
bool_subtype_base, 
eqtt_to_assert, 
assert_of_le_int, 
eqff_to_assert, 
iff_transitivity, 
iff_weakening_uiff, 
assert_of_bnot, 
choose-formula, 
mul_cancel_in_eq, 
choose_wf, 
nat_properties, 
decidable__le, 
full-omega-unsat, 
intformand_wf, 
intformnot_wf, 
intformle_wf, 
itermConstant_wf, 
itermVar_wf, 
istype-int, 
int_formula_prop_and_lemma, 
int_formula_prop_not_lemma, 
int_formula_prop_le_lemma, 
int_term_value_constant_lemma, 
int_term_value_var_lemma, 
int_formula_prop_wf, 
fact_wf, 
subtract_wf, 
itermSubtract_wf, 
int_term_value_subtract_lemma, 
decidable__equal_int, 
multiply-is-int-iff, 
intformeq_wf, 
itermMultiply_wf, 
int_formula_prop_eq_lemma, 
int_term_value_mul_lemma, 
false_wf
Rules used in proof : 
cut, 
introduction, 
extract_by_obid, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation_alt, 
hypothesis, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
productElimination, 
independent_isectElimination, 
setElimination, 
rename, 
because_Cache, 
equalityTransitivity, 
equalitySymmetry, 
inhabitedIsType, 
sqequalRule, 
functionIsType, 
independent_functionElimination, 
voidElimination, 
dependent_functionElimination, 
unionElimination, 
instantiate, 
cumulativity, 
independent_pairFormation, 
lambdaFormation_alt, 
multiplyEquality, 
dependent_set_memberEquality_alt, 
natural_numberEquality, 
approximateComputation, 
dependent_pairFormation_alt, 
lambdaEquality_alt, 
int_eqEquality, 
isect_memberEquality_alt, 
universeIsType, 
productIsType, 
applyEquality, 
pointwiseFunctionality, 
promote_hyp, 
baseApply, 
closedConclusion, 
baseClosed
Latex:
\mforall{}[m,n:\mBbbN{}].    C(m;n)  =  (choose(n;m)  *  (m)!)  supposing  m  \mleq{}  n
Date html generated:
2019_10_15-AM-11_21_41
Last ObjectModification:
2018_11_30-PM-01_15_46
Theory : general
Home
Index