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 A070825 One half of product of first n+1 Lucas numbers A000032. 12
 1, 1, 3, 12, 84, 924, 16632, 482328, 22669416, 1722875616, 211913700768, 42170826452832, 13579006117811904, 7074662187380001984, 5963940223961341672512, 8134814465483270041306368 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..90 R. Grünwald, E. Heidel, A. Strätz, M. Sünkel and R. Terbach, Induction on Number Series, Fakultät fur Wirtschaftsinformatik und Angewandte Informatik, Otto-Friedrich-Universität Bamberg, 2012. - N. J. A. Sloane, Feb 07 2013 FORMULA a(n) = (Product_{k=0..n} L(n))/2 with L(n) := A000032(n). Sum_{n>=0} 1/a(n) = 1 + A101690. - Amiram Eldar, Nov 09 2020 MATHEMATICA FoldList[Times, LucasL[Range[0, 20]]]/2 (* or *) Table[Round[GoldenRatio^(n(n+1)/2) QPochhammer[-1, GoldenRatio-2, n+1]]/2, {n, 0, 20}] (* Vladimir Reshetnikov, Sep 15 2016 *) PROG (PARI) a(n) = prod(k=0, n, fibonacci(k+1)+fibonacci(k-1))/2; \\ Michel Marcus, Mar 18 2016 (MAGMA) [1] cat [&*[Lucas(i+1): i in [0..n]]: n in [0..20]]; // Vincenzo Librandi, Sep 15 2016 CROSSREFS Cf. A003266 (for Fibonacci), A003046 (for Catalan), A101690, A135407, A218490. Sequence in context: A147835 A032183 A225905 * A232934 A077047 A074505 Adjacent sequences:  A070822 A070823 A070824 * A070826 A070827 A070828 KEYWORD nonn,easy AUTHOR Wolfdieter Lang, May 10 2002 STATUS approved

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Last modified April 15 20:35 EDT 2021. Contains 342977 sequences. (Running on oeis4.)