let x be set ; ( not x in 16 or x = 0 or x = 1 or x = 2 or x = 3 or x = 4 or x = 5 or x = 6 or x = 7 or x = 8 or x = 9 or x = 10 or x = 11 or x = 12 or x = 13 or x = 14 or x = 15 )
assume
x in 16
; ( x = 0 or x = 1 or x = 2 or x = 3 or x = 4 or x = 5 or x = 6 or x = 7 or x = 8 or x = 9 or x = 10 or x = 11 or x = 12 or x = 13 or x = 14 or x = 15 )
then
( x = 0 or ( x in Seg 16 & x <> 16 ) )
by th3;
hence
( x = 0 or x = 1 or x = 2 or x = 3 or x = 4 or x = 5 or x = 6 or x = 7 or x = 8 or x = 9 or x = 10 or x = 11 or x = 12 or x = 13 or x = 14 or x = 15 )
by Lmseg16a; verum