Letters that make prefix notation
a, o, e, f, n, p, r, t, i, x are letters that make 'prefix notation'
Words within prefix notation
tat, prefix, re, ti, PR, ref, Tati, at, IX, TAT, on, ix, not, no, fix, notation, Io, ion, Re, At, No, Pr, Ta, Ti are words within 'prefix notation'