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A035105 a(n) = LCM of Fibonacci sequence {F_1,...,F_n}.

%I A035105 #41 Jul 18 2022 03:09:39
%S A035105 1,1,2,6,30,120,1560,10920,185640,2042040,181741560,1090449360,
%T A035105 254074700880,7368166325520,449458145856720,21124532855265840,
%U A035105 33735878969859546480,640981700427331383120,2679944489486672512824720,109877724068953573025813520
%N A035105 a(n) = LCM of Fibonacci sequence {F_1,...,F_n}.
%H A035105 Alois P. Heinz, <a href="/A035105/b035105.txt">Table of n, a(n) for n = 1..124</a>
%H A035105 Yuri V. Matiyasevich and Richard K. Guy, <a href="https://doi.org/10.1080/00029890.1986.11971904">A new formula for Pi</a>, The American Mathematical Monthly, Vol 93, No. 8 (1986), pp. 631-635.
%H A035105 Carlo Sanna, <a href="https://arxiv.org/abs/2007.13330">On the l.c.m. of shifted Fibonacci numbers</a>, arXiv:2007.13330 [math.NT], 2020.
%H A035105 <a href="/index/Lc#lcm">Index entries for sequences related to LCM's</a>
%F A035105 log(a(n)) ~ 3*n^2*log(phi)/Pi^2, where phi is the golden ratio, or equivalently lim_{n->oo} sqrt(6*log(A003266(n))/log(a(n))) = Pi. - _Amiram Eldar_, Jan 30 2019
%p A035105 a:= proc(n) option remember; `if`(n=1, 1,
%p A035105       ilcm(a(n-1), combinat[fibonacci](n)))
%p A035105     end:
%p A035105 seq(a(n), n=1..25);  # _Alois P. Heinz_, Feb 12 2018
%t A035105 a[ n_ ] := LCM@@Table[ Fibonacci[ k ], {k, 1, n} ]
%t A035105 With[{fibs=Fibonacci[Range[20]]},Table[LCM@@Take[fibs,n],{n, Length[ fibs]}]] (* _Harvey P. Dale_, Apr 29 2019 *)
%o A035105 (PARI) a(n)=lcm(apply(fibonacci,[1..n])) \\ _Charles R Greathouse IV_, Oct 07 2016
%o A035105 (Python)
%o A035105 from math import lcm
%o A035105 from sympy import fibonacci
%o A035105 def A035105(n): return lcm(*(fibonacci(i) for i in range(1,n+1))) # _Chai Wah Wu_, Jul 17 2022
%Y A035105 Cf. A000045, A001622, A003266, A059248.
%K A035105 nonn,easy
%O A035105 1,3
%A A035105 Fred Schwab (fschwab(AT)nrao.edu)