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A099946 a(n) = lcm{1, 2, ..., n}/(n*(n-1)), n >= 2.

%I A099946 #48 Oct 27 2023 21:55:01
%S A099946 1,1,1,3,2,10,15,35,28,252,210,2310,1980,1716,3003,45045,40040,680680,
%T A099946 612612,554268,503880,10581480,9699690,44618574,41186376,114406600,
%U A099946 106234700,2868336900,2677114440,77636318760,145568097675,136745788725
%N A099946 a(n) = lcm{1, 2, ..., n}/(n*(n-1)), n >= 2.
%H A099946 Alois P. Heinz, <a href="/A099946/b099946.txt">Table of n, a(n) for n = 2..1000</a> (first 99 terms from Luke March)
%F A099946 a(n) = A003418(n)/(n*(n-1)) = A003418(n)/A002378(n-1), n >= 2.
%p A099946 a:= n-> ilcm(seq(k,k=1..n))/n/(n-1): seq(a(n), n=2..37); # _Emeric Deutsch_, Jun 13 2005
%t A099946 Table[LCM@@Range[n]/(n(n-1)), {n,2,40}] (* _Harvey P. Dale_, Jan 14 2011 *)
%o A099946 (Python)
%o A099946 from math import gcd
%o A099946 def lcm(a, b):
%o A099946     return (a * b) // gcd(a, b)
%o A099946 def f(lim):
%o A099946     l = 1
%o A099946     for n in range(2, lim + 1):
%o A099946         l = lcm(n, l)
%o A099946         print(n, l // (n * (n - 1)))
%o A099946 f(100) # _Luke March_, Jul 23 2014
%o A099946 (PARI) a(n) = lcm(vector(n, i, i))/(n*(n-1)); \\ _Michel Marcus_, Jul 25 2014
%Y A099946 Cf. A002378, A002944, A003418, A025558.
%K A099946 nonn,easy
%O A099946 2,4
%A A099946 _N. J. A. Sloane_, Nov 12 2004
%E A099946 More terms from _Emeric Deutsch_, Jun 13 2005