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%I #29 Oct 27 2023 22:00:44
%S 2,4,12,24,120,120,840,1680,5040,5040,55440,55440,720720,720720,
%T 720720,1441440,24504480,24504480,465585120,465585120,465585120,
%U 465585120,10708457760,10708457760,53542288800,53542288800,160626866400,160626866400,4658179125600
%N Least common multiple of {2, 4, 6, ..., 2n}.
%C Gcd(A025547(n), a(n)) = A025547(floor((n+1)/2)). - _Reinhard Zumkeller_, Apr 25 2011
%D A. Murthy, Some new Smarandache sequences, functions and partitions, Smarandache Notions Journal Vol. 11 N. 1-2-3 Spring 2000 (but beware errors).
%H T. D. Noe, <a href="/A051426/b051426.txt">Table of n, a(n) for n = 1..500</a>
%H <a href="/index/Lc#lcm">Index entries for sequences related to lcm's</a>
%F a(n) = a(n-1)*lcm(a(n-1),2n) = a(n-1)* A014963(n). - _Zak Seidov_, Aug 01 2009
%e a(3) = lcm{2,4,6} = 12;
%e a(7) = lcm{2,4,6,8,10,12,14} = 840.
%t SZ={2};n=2;L=2;Do[L=LCM[L,2n];AppendTo[SZ,L];n++,{99}];SZ (* _Zak Seidov_, Aug 01 2009 *)
%t Table[LCM@@Range[2,2n,2],{n,30}] (* _Harvey P. Dale_, Oct 09 2011 *)
%o (Haskell)
%o a051426 n = foldl lcm 1 [2,4..2*n] -- _Reinhard Zumkeller_, Apr 25 2011
%o (PARI) a(n)=2*lcm([1..n]) \\ _Charles R Greathouse IV_, Oct 28 2016
%Y Cf. A003418, A025547.
%K easy,nice,nonn
%O 1,1
%A _Asher Auel_
%E a(6), a(7) and a(8) corrected by _T. D. Noe_, Feb 08 2008
%E Corrected the example, which did not reflect the sequence values provided. - Michael Davies (mykdavies+oeis(AT)gmail.com), Oct 10 2008
%E Edited by _N. J. A. Sloane_, Jul 31 2009 at the suggestion of _R. J. Mathar_
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