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 A051426 Least common multiple of {2, 4, 6, ..., 2n}. 4
 2, 4, 12, 24, 120, 120, 840, 1680, 5040, 5040, 55440, 55440, 720720, 720720, 720720, 1441440, 24504480, 24504480, 465585120, 465585120, 465585120, 465585120, 10708457760, 10708457760, 53542288800, 53542288800, 160626866400, 160626866400, 4658179125600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Gcd(A025547(n), a(n)) = A025547(floor((n+1)/2)). - Reinhard Zumkeller, Apr 25 2011 REFERENCES A. Murthy, Some new Smarandache sequences, functions and partitions, Smarandache Notions Journal Vol. 11 N. 1-2-3 Spring 2000 (but beware errors). LINKS T. D. Noe, Table of n, a(n) for n = 1..500 FORMULA a(n) = a(n-1)*lcm(a(n-1),2n) = a(n-1)* A014963(n). - Zak Seidov, Aug 01 2009 EXAMPLE a(3) = lcm{2,4,6} = 12; a(7) = lcm{2,4,6,8,10,12,14} = 840. MATHEMATICA SZ={2}; n=2; L=2; Do[L=LCM[L, 2n]; AppendTo[SZ, L]; n++, {99}]; SZ (* Zak Seidov, Aug 01 2009 *) Table[LCM@@Range[2, 2n, 2], {n, 30}] (* Harvey P. Dale, Oct 09 2011 *) PROG (Haskell) a051426 n = foldl lcm 1 [2, 4..2*n] -- Reinhard Zumkeller, Apr 25 2011 (PARI) a(n)=2*lcm([1..n]) \\ Charles R Greathouse IV, Oct 28 2016 CROSSREFS Cf. A003418, A025547. Sequence in context: A096421 A066843 A051905 * A048148 A080375 A136253 Adjacent sequences:  A051423 A051424 A051425 * A051427 A051428 A051429 KEYWORD easy,nice,nonn AUTHOR Asher Auel (asher.auel(AT)reed.edu) EXTENSIONS a(6), a(7) and a(8) corrected by T. D. Noe, Feb 08 2008 Corrected the example, which did not reflect the sequence values provided. - Michael Davies (mykdavies+oeis(AT)gmail.com), Oct 10 2008 Edited by N. J. A. Sloane, Jul 31 2009 at the suggestion of R. J. Mathar STATUS approved

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Last modified June 24 00:06 EDT 2021. Contains 345403 sequences. (Running on oeis4.)