Structure gcdTheory
signature gcdTheory =
sig
type thm = Thm.thm
(* Definitions *)
val gcd_curried_def : thm
val gcd_tupled_primitive_def : thm
val is_gcd_def : thm
(* Theorems *)
val FACTOR_OUT_GCD : thm
val GCD_0L : thm
val GCD_0R : thm
val GCD_ADD_L : thm
val GCD_ADD_R : thm
val GCD_EFFICIENTLY : thm
val GCD_EQ_0 : thm
val GCD_IS_GCD : thm
val GCD_REF : thm
val GCD_SYM : thm
val IS_GCD_0R : thm
val IS_GCD_MINUS_L : thm
val IS_GCD_MINUS_R : thm
val IS_GCD_REF : thm
val IS_GCD_SYM : thm
val IS_GCD_UNIQUE : thm
val LINEAR_GCD : thm
val L_EUCLIDES : thm
val PRIME_GCD : thm
val PRIME_IS_GCD : thm
val P_EUCLIDES : thm
val gcd_def : thm
val gcd_ind : thm
val gcd_grammars : type_grammar.grammar * term_grammar.grammar
(*
[divides] Parent theory of "gcd"
[option] Parent theory of "gcd"
[gcd_curried_def] Definition
|- !x x1. gcd x x1 = gcd_tupled (x,x1)
[gcd_tupled_primitive_def] Definition
|- gcd_tupled =
WFREC
(@R.
WF R /\ (!x y. ~(y <= x) ==> R (SUC x,y - x) (SUC x,SUC y)) /\
!x y. y <= x ==> R (x - y,SUC y) (SUC x,SUC y))
(\gcd_tupled a.
case a of
(0,y) -> I y
|| (SUC x,0) -> I (SUC x)
|| (SUC x,SUC y') ->
I
(if y' <= x then
gcd_tupled (x - y',SUC y')
else
gcd_tupled (SUC x,y' - x)))
[is_gcd_def] Definition
|- !a b c.
is_gcd a b c =
divides c a /\ divides c b /\
!d. divides d a /\ divides d b ==> divides d c
[FACTOR_OUT_GCD] Theorem
|- !n m.
~(n = 0) /\ ~(m = 0) ==>
?p q. (n = p * gcd n m) /\ (m = q * gcd n m) /\ (gcd p q = 1)
[GCD_0L] Theorem
|- !a. gcd 0 a = a
[GCD_0R] Theorem
|- !a. gcd a 0 = a
[GCD_ADD_L] Theorem
|- !a b. gcd (a + b) a = gcd a b
[GCD_ADD_R] Theorem
|- !a b. gcd a (a + b) = gcd a b
[GCD_EFFICIENTLY] Theorem
|- !a b. gcd a b = (if a = 0 then b else gcd (b MOD a) a)
[GCD_EQ_0] Theorem
|- !n m. (gcd n m = 0) = (n = 0) /\ (m = 0)
[GCD_IS_GCD] Theorem
|- !a b. is_gcd a b (gcd a b)
[GCD_REF] Theorem
|- !a. gcd a a = a
[GCD_SYM] Theorem
|- !a b. gcd a b = gcd b a
[IS_GCD_0R] Theorem
|- !a. is_gcd 0 a a
[IS_GCD_MINUS_L] Theorem
|- !a b c. b <= a /\ is_gcd (a - b) b c ==> is_gcd a b c
[IS_GCD_MINUS_R] Theorem
|- !a b c. a <= b /\ is_gcd a (b - a) c ==> is_gcd a b c
[IS_GCD_REF] Theorem
|- !a. is_gcd a a a
[IS_GCD_SYM] Theorem
|- !a b c. is_gcd a b c = is_gcd b a c
[IS_GCD_UNIQUE] Theorem
|- !a b c d. is_gcd a b c /\ is_gcd a b d ==> (c = d)
[LINEAR_GCD] Theorem
|- !n m. ~(n = 0) ==> ?p q. p * n = q * m + gcd m n
[L_EUCLIDES] Theorem
|- !a b c. (gcd a b = 1) /\ divides b (a * c) ==> divides b c
[PRIME_GCD] Theorem
|- !p b. prime p ==> divides p b \/ (gcd p b = 1)
[PRIME_IS_GCD] Theorem
|- !p b. prime p ==> divides p b \/ is_gcd p b 1
[P_EUCLIDES] Theorem
|- !p a b. prime p /\ divides p (a * b) ==> divides p a \/ divides p b
[gcd_def] Theorem
|- (gcd 0 y = y) /\ (gcd (SUC x) 0 = SUC x) /\
(gcd (SUC x) (SUC y) =
(if y <= x then gcd (x - y) (SUC y) else gcd (SUC x) (y - x)))
[gcd_ind] Theorem
|- !P.
(!y. P 0 y) /\ (!x. P (SUC x) 0) /\
(!x y.
(~(y <= x) ==> P (SUC x) (y - x)) /\ (y <= x ==> P (x - y) (SUC y)) ==>
P (SUC x) (SUC y)) ==>
!v v1. P v v1
*)
end
HOL 4, Kananaskis-3