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%I #15 Dec 12 2017 00:51:31
%S 1,1,2,4,8,64,20480,21558722560,1896327099254067272089600
%N a(1) = 1; a(n+1) = lcm(Sum_{k=1..n} a(k), Product_{k=1..n} a(k)).
%H Reinhard Zumkeller, <a href="/A058345/b058345.txt">Table of n, a(n) for n = 1..13</a>
%e a(6) = lcm(1 + 1 + 2 + 4 + 8, 1*1*2*4*8) = lcm(16, 64) = 64.
%t Nest[Append[#, LCM[Total@ #, Times @@ #]] &, {1}, 13] (* _Michael De Vlieger_, Dec 11 2017 *)
%o (Haskell)
%o a058345 n = a058345_list !! (n-1)
%o a058345_list = 1 : f 1 1 where
%o f u v = w : f (u * w) (v + w) where w = lcm u v
%o -- _Reinhard Zumkeller_, Mar 20 2014
%Y Cf. A057194.
%K nonn
%O 1,3
%A _Leroy Quet_, Dec 14 2000
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