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 A193181 a(n) = lcm(f(1),f(2),...,f(n)) with f(x) = x^2+1. 3
 2, 10, 10, 170, 2210, 81770, 408850, 408850, 16762850, 1693047850, 103275918850, 2995001646650, 2995001646650, 590015324390050, 66671731656075650, 17134635035611442050, 17134635035611442050, 17134635035611442050, 3101368941445671011050 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS log(a(n)) = n*log(n)+B*n+o(n); B=-0.066275634213060706383563177025. All prime factors of a(n) are in A002313. - Robert Israel, Mar 13 2016 LINKS Robert Israel, Table of n, a(n) for n = 1..388 J. Cilleruelo, The least common multiple of a quadratic sequence, arXiv:1001.3438 [math.NT], 2010. J. Cilleruelo, The least common multiple of a quadratic sequence, Compos. Math. 147 (2011), no. 4, 1129-1150. Bakir Farhi, Nontrivial lower bounds for the least common multiple of some finite sequences of integers, J. Number Theory, 125 (2007), p. 393-411. Steven Finch, Cilleruelo's LCM Constants, 2013. [Cached copy, with permission of the author] Juanjo Rué, Paulius Šarka, and Ana Zumalacárregui, On the error term of the logarithm of the lcm of a quadratic sequence, arXiv:1110.0939 [math.NT], 2011. Juanjo Rué, Paulius Šarka, and Ana Zumalacárregui, On the error term of the logarithm of the lcm of a quadratic sequence, Journal de théorie des nombres de Bordeaux, 25 no. 2 (2013), p. 457-470. MAPLE a[0]:= 1: for n from 1 to 30 do a[n]:= ilcm(a[n-1], n^2+1) od: seq(a[i], i=1..30); # Robert Israel, Mar 13 2016 MATHEMATICA f[x_] := x^2+1; a[1] = f[1]; a[n_] := a[n] = LCM[f[n], a[n-1]]; Table[a[n], {n, 20}] PROG (PARI) a(n)=lcm(vector(n, k, k^2+1)) \\ Charles R Greathouse IV, Jul 26 2013 CROSSREFS Cf. A002313, A002522, A003418. Sequence in context: A066394 A232500 A033466 * A222638 A299982 A089601 Adjacent sequences:  A193178 A193179 A193180 * A193182 A193183 A193184 KEYWORD nonn AUTHOR José María Grau Ribas, Jul 17 2011 STATUS approved

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Last modified October 15 09:22 EDT 2019. Contains 328026 sequences. (Running on oeis4.)