A058345 a(1) = 1; a(n+1) = lcm(Sum_{k=1..n} a(k), Product_{k=1..n} a(k)).

1, 1, 2, 4, 8, 64, 20480, 21558722560, 1896327099254067272089600

Offset

1,3

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..13

Example

a(6) = lcm(1 + 1 + 2 + 4 + 8, 1*1*2*4*8) = lcm(16, 64) = 64.

Mathematica

Nest[Append[#, LCM[Total@ #, Times @@ #]] &, {1}, 13] (* Michael De Vlieger, Dec 11 2017 *)

Prog

(Haskell)
a058345 n = a058345_list !! (n-1)
a058345_list = 1 : f 1 1 where
   f u v = w : f (u * w) (v + w) where w = lcm u v
-- Reinhard Zumkeller, Mar 20 2014

Crossrefs

Cf. A057194.

Sequence in context: A320898 A068994 A167182 * A093843 A270372 A018507

Adjacent sequences: A058342 A058343 A058344 * A058346 A058347 A058348

Keyword

nonn

Author

Leroy Quet, Dec 14 2000

Status

approved