Page 131 - Numbertheory

@ @@@lb¨a@À@óïŽbŽÿa@óåè ¾a

: ()

3 × 4 × 5 × 6 × ... × n +1 = n +1
2345 n2

.n

1998 116 ( ) [British JMC 1998] ( )
43 ( ) 42 ( )
1001 ( )

1998 : ( )

1998 = 2 × 999 = 2× 32 ×111 = 2 × 33 × 37

. 2 + 3 + 37 = 42 37 3 2

1998 [AHSME 1998] ( )

. 17 ( ) 15 ( ) 8 ()
47 ( )

1998 : ( )

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