reconsider s1 = s, t1 = t as Element of Funcs ((Seg n),BOOLEAN) by FINSEQ_2:93;
s1 'xor' t1 is Element of Funcs ((Seg n),BOOLEAN) by FUNCT_2:8;
hence Op-XOR (t,) is Element of n -tuples_on BOOLEAN by FINSEQ_2:93; :: thesis: verum