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a(1) = 1 and then numbers such that the product of n terms starting with the n-th term is an n-th power. The smallest numbers not occurring earlier are used first.
1

%I #7 Dec 05 2013 19:56:04

%S 1,2,8,3,9,4,12,5,360000,6,90,7,28235760,10,504,11,450153650100,13,

%T 17637403357173600000,14,25740,15,360360,16,215255040,17,

%U 33593154183197105261619254400,18,16278356694600,19

%N a(1) = 1 and then numbers such that the product of n terms starting with the n-th term is an n-th power. The smallest numbers not occurring earlier are used first.

%e as a(3) = 8 choose a(4) = 3 ( smallest number not occurring earlier) and a(5) = 9 to satisfy the requirement. The product of three terms starting with a(3) is 8*3*9 = 216 = 6^3.

%Y Cf. A082237.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Apr 10 2003

%E Corrected and extended by _David Wasserman_, Aug 26 2004