let n be Nat; ( 0 <= n & n < (((2 * 3) * 5) * 7) * 11 implies 76 <= card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11))) )
assume A1:
( 0 <= n & n < (((2 * 3) * 5) * 7) * 11 )
; 76 <= card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11)))
set S = seq (n,100);
set M2 = multiples 2;
set M3 = multiples 3;
set M5 = multiples 5;
set M7 = multiples 7;
set M11 = multiples 11;
set M2357 = (((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7);
set M = ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11);
assume A2:
card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11))) < 76
; contradiction
((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11) = ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ ((multiples 11) \ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)))
by XBOOLE_1:39;
then A3:
(seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11)) = ((seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7))) \/ ((seq (n,100)) /\ ((multiples 11) \ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7))))
by XBOOLE_1:23;
(seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) misses (seq (n,100)) /\ ((multiples 11) \ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)))
by XBOOLE_1:76, XBOOLE_1:79;
then A4:
card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11))) = (card ((seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)))) + (card ((seq (n,100)) /\ ((multiples 11) \ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)))))
by A3, CARD_2:40;
card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11))) < 75 + 1
by A2;
then A5:
( (card ((seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)))) + 0 <= card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11))) & card ((seq (n,100)) /\ (((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) \/ (multiples 11))) <= 75 )
by NAT_1:13, A4, XREAL_1:7;
then A6:
card ((seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7))) <= 75
by XXREAL_0:2;
card ((seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7))) >= 75
by Th94;
then A7:
card ((seq (n,100)) /\ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7))) = 75
by A6, XXREAL_0:1;
then
( n mod 210 = 9 or n mod 210 = 10 or n mod 210 = 99 or n mod 210 = 100 )
by Th94;
then consider t being Nat such that
A8:
( ( n = (210 * t) + 9 & 9 < 210 ) or ( n = (210 * t) + 10 & 10 < 210 ) or ( n = (210 * t) + 99 & 99 < 210 ) or ( n = (210 * t) + 100 & 100 < 210 ) )
by NAT_D:def 2;
A9:
(seq (n,100)) /\ ((multiples 11) \ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7))) = {}
by XREAL_1:8, A4, A5, A7;
A10:
t < 10 + 1
A11:
for i, k being Nat st i + 1 < k & k <= i + 100 & k in (multiples 11) \ ((((multiples 2) \/ (multiples 3)) \/ (multiples 5)) \/ (multiples 7)) holds
( i <> n & i + 1 <> n )
t <= 10
by A10, NAT_1:13;
then
not not t = 0 & ... & not t = 10
;
per cases then
( t = 0 or t = 1 or t = 2 or t = 3 or t = 4 or t = 5 or t = 6 or t = 7 or t = 8 or t = 9 or t = 10 )
;
end;