@ @RS@ @óïbÿa@‡ÉÜa@ú†bjà@ @ VARIOUS () ) (A,E,I,O,U A,I,O,U 4 7 . .V,R,S . 4 × 3 × 3 × 2 × 2 ×1×1 = 144 () A =m f :A→B ( ) B =n .B A m ≤n m >n .a1 .a2 .0 n . A = {a1,a2, … ,am } a3 n −1 . n −2 .n × (n − 1)× (n − 2) × × (n − m + 1)