Selected Objects
| COM | simple_mul_factsVERSION 
 | 1 | 
| THM | nat_prod_one_iff_factors_one 
 |  x,y:  . x  y = 1   x = 1 & y = 1 | 
| THM | prod_zero_iff_factor_zero 
 |  a,b:  . a  b = 0   a = 0  b = 0 | 
| THM | mul_nat_com 
 |  a,b,c,d:  . a = b   c = d   a  c = d  b    | 
| THM | nat_factor_cancel_rw 
 |  a,b:  , n:   . n  a  n  b   a  b | 
| THM | mul_cancel_in_eq1 
 |  a,b:  , n:    . n  a = n  b   a = b | 
| THM | mul_cancel_in_eq2 
 |  a,b:  , m,n:    . m = n   (m  a = n  b   a = b) | 
| THM | le_mul_rt_by_pos 
 |  x,y:  , z:   . x  y   x  y  z | 
| THM | factor_bound 
 |  k:   , n:  , x,y:  . k  x+n = k  y   x  y | 
| THM | lt_mul_rt_by_pos 
 |  x,y:  , z:   . x<y   x<y  z | 
| THM | factors_bound 
 |  i,j:   . i  i  j & j  i  j | 
| THM | pos_mul_arg_boundsNat 
 |  a,b:  . 0<a  b   0<a & 0<b | 
| THM | pos_mul_arg_boundsNat2 
 |  i,j:  . 0<i  j   i  i  j & j  i  j | 
| THM | factor_smaller 
 |  i:{2...}, j:{1...}. j<i  j | 
| THM | factor_smaller2 
 |  i:{2...}, j:   . j<i  j | 
| THM | factors_smaller 
 |  i,j:{2...}. i<i  j & j<i  j | 
| THM | factors_smaller2 
 |  k:   , i:{2..k  }, j:  . i  j = k   2  j < k & i<k | 
| THM | mul_nat_plus 
 |  x,y:   . x  y     | 
| THM | divides_def_on_nat 
 | a divides b (specialized to natural numbers) 
  a,b:  . a | b   (  c:  . b = a  c) | 
| THM | only_one_nat_divs_one 
 |  b:  . b | 1   b = 1 | 
| THM | div_inverts_nat_mul 
 |  x,y:  , z:   . x = y  z   (x  z) = y | 
| THM | div_inverts_nat_mul2 
 |  x:   , y,z:  . x = y  z   (x  z) = y | 
| THM | prime_nat 
 |  x:  . prime(x)   2  x &  (  i:{2..x  }. i | x) | 
| def | prime_nats 
 | Prime  == {x:  | prime(x) } | 
| THM | natprimes_lb 
 |  x:  . prime(x)   2  x | 
| THM | natprime_nondivs 
 |  x:  . prime(x)   (  i:{2..x  }.  i | x) | 
| THM | nonprime_nat 
 |  x:  .  prime(x)   x<2  (  i,j:{2..x  }. x = i  j) | 
| THM | composite_with_prime_factor 
 |  x:{2...}.  prime(x)   (  i,j:{2..x  }. x = i  j & prime(i)) | 
| THM | prime_or_smaller_prime_factor2 
 |  x:{2...}.  p:{2...}, c:{1...}. p  x & prime(p) & x = p  c | 
| THM | prime_or_smaller_prime_factor 
 | A number bigger than 1 is divisible by a prime. 
  x:{2...}.  p:{2...}. p  x & prime(p) & p | x | 
| THM | prime_neg 
 |  y:  . prime(-y)   prime(y) | 
| THM | decidable__prime 
 |  x:  . Dec(prime(x)) | 
| THM | prime_decider_exists 
 |  !  {p:(     )|  x:  . p(x)   prime(x) } | 
| def | prime_decider 
 | Boolean decider for primeness implicit in Thm*  !  {p:(     )|  x:  . p(x)   prime(x) } is_prime(x) == prime_decider_exists{1:l}(x)
 | 
| THM | no_nat_prime_divs_one 
 |  b:  . b | 1     prime(b) | 
| THM | no_prime_divs_one 
 | One has no prime divisors. 
  b:  . b | 1     prime(b) | 
| THM | no_prime_divs_one_b 
 | One has no prime divisors. 
  b:  . prime(b)     b | 1 | 
| THM | prime_nat_divby_self_only 
 |  x:{2...}, y:  . prime(y)   x | y   x = y    | 
| THM | prime_among_factors 
 | Factoring a prime always includes the prime itself. 
  a,b:  . prime(a  b)   a  b = a  a  b = b |