let a, b, c, h be Integer; ( h = ((a - b) * (a - c)) * (b - c) implies for S being Sierp45FS of a,b,c
for n being Nat st a,b,c are_mutually_distinct & n, numberR (a,b,c) are_congruent_mod 2 & n, numberR0 (a,b,c) are_congruent_mod 3 & ( for i being Nat st i in dom S holds
n,S . i are_congruent_mod (Sgm (PrimeDivisors>3 h)) . i ) holds
a + n,b + n are_coprime )
assume A1:
h = ((a - b) * (a - c)) * (b - c)
; for S being Sierp45FS of a,b,c
for n being Nat st a,b,c are_mutually_distinct & n, numberR (a,b,c) are_congruent_mod 2 & n, numberR0 (a,b,c) are_congruent_mod 3 & ( for i being Nat st i in dom S holds
n,S . i are_congruent_mod (Sgm (PrimeDivisors>3 h)) . i ) holds
a + n,b + n are_coprime
set r = numberR (a,b,c);
set r0 = numberR0 (a,b,c);
set SGM = Sgm (PrimeDivisors>3 h);
let S be Sierp45FS of a,b,c; for n being Nat st a,b,c are_mutually_distinct & n, numberR (a,b,c) are_congruent_mod 2 & n, numberR0 (a,b,c) are_congruent_mod 3 & ( for i being Nat st i in dom S holds
n,S . i are_congruent_mod (Sgm (PrimeDivisors>3 h)) . i ) holds
a + n,b + n are_coprime
let n be Nat; ( a,b,c are_mutually_distinct & n, numberR (a,b,c) are_congruent_mod 2 & n, numberR0 (a,b,c) are_congruent_mod 3 & ( for i being Nat st i in dom S holds
n,S . i are_congruent_mod (Sgm (PrimeDivisors>3 h)) . i ) implies a + n,b + n are_coprime )
assume that
A2:
a,b,c are_mutually_distinct
and
A3:
n, numberR (a,b,c) are_congruent_mod 2
and
A4:
n, numberR0 (a,b,c) are_congruent_mod 3
and
A5:
for i being Nat st i in dom S holds
n,S . i are_congruent_mod (Sgm (PrimeDivisors>3 h)) . i
; a + n,b + n are_coprime
assume A6:
not a + n,b + n are_coprime
; contradiction
consider q being Prime such that
A7:
( q divides |.(a + n).| & q divides |.(b + n).| )
by A6, Th9, PYTHTRIP:def 2;
A8:
( q divides a + n & q divides b + n )
by A7, Th4;
then A9:
q divides (a + n) - (b + n)
by INT_5:1;
A10:
h = (a - b) * ((a - c) * (b - c))
by A1;
two_or_more_are_odd_among a + n,b + n,c + n
proof
numberR (
a,
b,
c),
n are_congruent_mod 2
by A3, INT_1:14;
then A11:
(
a + (numberR (a,b,c)),
a + n are_congruent_mod 2 &
b + (numberR (a,b,c)),
b + n are_congruent_mod 2 &
c + (numberR (a,b,c)),
c + n are_congruent_mod 2 )
;
two_or_more_are_odd_among a + (numberR (a,b,c)),
b + (numberR (a,b,c)),
c + (numberR (a,b,c))
by Th33;
hence
two_or_more_are_odd_among a + n,
b + n,
c + n
by A11;
verum
end;
then A12:
q <> 2
by A8;
a + n,b + n,c + n at_least_two_are_not_divisible_by 3
proof
A13:
n mod 3
= (numberR0 (a,b,c)) mod 3
by A4, NAT_D:64;
A14:
(a + (numberR0 (a,b,c))) mod 3
= ((a mod 3) + ((numberR0 (a,b,c)) mod 3)) mod 3
by NAT_D:66;
A15:
(b + (numberR0 (a,b,c))) mod 3
= ((b mod 3) + ((numberR0 (a,b,c)) mod 3)) mod 3
by NAT_D:66;
A16:
(c + (numberR0 (a,b,c))) mod 3
= ((c mod 3) + ((numberR0 (a,b,c)) mod 3)) mod 3
by NAT_D:66;
A17:
(a + n) mod 3
= ((a mod 3) + (n mod 3)) mod 3
by NAT_D:66;
A18:
(b + n) mod 3
= ((b mod 3) + (n mod 3)) mod 3
by NAT_D:66;
A19:
(c + n) mod 3
= ((c mod 3) + (n mod 3)) mod 3
by NAT_D:66;
now ( ( not 3 divides a + (numberR0 (a,b,c)) & not 3 divides b + (numberR0 (a,b,c)) & 3 divides c + (numberR0 (a,b,c)) & not 3 divides a + n & not 3 divides b + n & 3 divides c + n ) or ( not 3 divides a + (numberR0 (a,b,c)) & 3 divides b + (numberR0 (a,b,c)) & not 3 divides c + (numberR0 (a,b,c)) & not 3 divides a + n & 3 divides b + n & not 3 divides c + n ) or ( 3 divides a + (numberR0 (a,b,c)) & not 3 divides b + (numberR0 (a,b,c)) & not 3 divides c + (numberR0 (a,b,c)) & 3 divides a + n & not 3 divides b + n & not 3 divides c + n ) or ( not 3 divides a + (numberR0 (a,b,c)) & not 3 divides b + (numberR0 (a,b,c)) & not 3 divides c + (numberR0 (a,b,c)) & not 3 divides a + n & not 3 divides b + n & not 3 divides c + n ) )
a + (numberR0 (a,b,c)),
b + (numberR0 (a,b,c)),
c + (numberR0 (a,b,c)) at_least_two_are_not_divisible_by 3
by Th34;
per cases then
( ( not 3 divides a + (numberR0 (a,b,c)) & not 3 divides b + (numberR0 (a,b,c)) & 3 divides c + (numberR0 (a,b,c)) ) or ( not 3 divides a + (numberR0 (a,b,c)) & 3 divides b + (numberR0 (a,b,c)) & not 3 divides c + (numberR0 (a,b,c)) ) or ( 3 divides a + (numberR0 (a,b,c)) & not 3 divides b + (numberR0 (a,b,c)) & not 3 divides c + (numberR0 (a,b,c)) ) or ( not 3 divides a + (numberR0 (a,b,c)) & not 3 divides b + (numberR0 (a,b,c)) & not 3 divides c + (numberR0 (a,b,c)) ) )
;
case
( not 3
divides a + (numberR0 (a,b,c)) & not 3
divides b + (numberR0 (a,b,c)) & 3
divides c + (numberR0 (a,b,c)) )
;
( not 3 divides a + n & not 3 divides b + n & 3 divides c + n )then
(
(a + (numberR0 (a,b,c))) mod 3
<> 0 &
(b + (numberR0 (a,b,c))) mod 3
<> 0 &
(c + (numberR0 (a,b,c))) mod 3
= 0 )
by INT_1:62;
hence
( not 3
divides a + n & not 3
divides b + n & 3
divides c + n )
by A13, A14, A15, A16, A17, A18, A19, INT_1:62;
verum end; case
( not 3
divides a + (numberR0 (a,b,c)) & 3
divides b + (numberR0 (a,b,c)) & not 3
divides c + (numberR0 (a,b,c)) )
;
( not 3 divides a + n & 3 divides b + n & not 3 divides c + n )then
(
(a + (numberR0 (a,b,c))) mod 3
<> 0 &
(b + (numberR0 (a,b,c))) mod 3
= 0 &
(c + (numberR0 (a,b,c))) mod 3
<> 0 )
by INT_1:62;
hence
( not 3
divides a + n & 3
divides b + n & not 3
divides c + n )
by A13, A14, A15, A16, A17, A18, A19, INT_1:62;
verum end; case
( 3
divides a + (numberR0 (a,b,c)) & not 3
divides b + (numberR0 (a,b,c)) & not 3
divides c + (numberR0 (a,b,c)) )
;
( 3 divides a + n & not 3 divides b + n & not 3 divides c + n )then
(
(a + (numberR0 (a,b,c))) mod 3
= 0 &
(b + (numberR0 (a,b,c))) mod 3
<> 0 &
(c + (numberR0 (a,b,c))) mod 3
<> 0 )
by INT_1:62;
hence
( 3
divides a + n & not 3
divides b + n & not 3
divides c + n )
by A13, A14, A15, A16, A17, A18, A19, INT_1:62;
verum end; case
( not 3
divides a + (numberR0 (a,b,c)) & not 3
divides b + (numberR0 (a,b,c)) & not 3
divides c + (numberR0 (a,b,c)) )
;
( not 3 divides a + n & not 3 divides b + n & not 3 divides c + n )then
(
(a + (numberR0 (a,b,c))) mod 3
<> 0 &
(b + (numberR0 (a,b,c))) mod 3
<> 0 &
(c + (numberR0 (a,b,c))) mod 3
<> 0 )
by INT_1:62;
hence
( not 3
divides a + n & not 3
divides b + n & not 3
divides c + n )
by A13, A14, A15, A16, A17, A18, A19, INT_1:62;
verum end; end; end;
hence
a + n,
b + n,
c + n at_least_two_are_not_divisible_by 3
;
verum
end;
then A20:
q <> 3
by A8;
consider h1 being Integer, F being FinSequence of NAT such that
A21:
h1 = ((a - b) * (a - c)) * (b - c)
and
A22:
F = Sgm (PrimeDivisors>3 h1)
and
A23:
len S = len F
and
A24:
for i being object st i in dom S holds
( not F . i divides a + (S . i) & not F . i divides b + (S . i) & not F . i divides c + (S . i) )
by A2, Def12;
( a - b <> 0 & a - c <> 0 & b - c <> 0 )
by A2;
then A25:
PrimeDivisors>3 h = rng (Sgm (PrimeDivisors>3 h))
by A1, FINSEQ_1:def 14;
now not q <= 3assume
q <= 3
;
contradictionthen
not not
q = 0 & ... & not
q = 3
;
hence
contradiction
by A12, A20, INT_2:def 4;
verum end;
then
q in PrimeDivisors>3 h
by A9, A10, Th38, INT_2:2;
then consider i being object such that
A26:
i in dom (Sgm (PrimeDivisors>3 h))
and
A27:
q = (Sgm (PrimeDivisors>3 h)) . i
by A25, FUNCT_1:def 3;
reconsider i = i as Nat by A26;
A28:
dom S = dom (Sgm (PrimeDivisors>3 h))
by A1, A21, A22, A23, FINSEQ_3:29;
then
n,S . i are_congruent_mod q
by A5, A26, A27;
then A29:
n + a,(S . i) + a are_congruent_mod q
;
( not q divides a + (S . i) & not q divides b + (S . i) & not q divides c + (S . i) )
by A1, A21, A22, A26, A27, A28, A24;
hence
contradiction
by A8, A29, Th19; verum