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        riddles >> medium >> LCM of "falling factorial"
        
(Message started by: O09 on Nov 6^th, 2009, 8:08pm)

Title: LCM of "falling factorial"
Post by O09 on Nov 6^th, 2009, 8:08pm

Let a(n,k)=lcm(n,n-1,n-2,n-k+1). Let m be the greatest integer k such that a(n,1)<a(n,2)<a(n,3)<...<a(n,k). Prove that m < 3*Sqrt(n) and m>k if n>k!+k