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%I #31 Jun 20 2019 02:58:18
%S 1,1,2,3,12,5,60,105,280,63,2520,385,27720,6435,8008,45045,720720,
%T 85085,12252240,2909907,3695120,1322685,232792560,37182145,1070845776,
%U 128707425,2974571600,717084225,80313433200,215656441,2329089562800
%N Least common multiple of integers less than and prime to n.
%C If n is a prime power, tau(a(n)) is the number of times n occurs in A034699. (If n is not a prime power, it does not occur in A034699.) - _Franklin T. Adams-Watters_, Apr 01 2008
%C a(n) = lcm(A038566(n,k): k = 1..A000010(n)). - _Reinhard Zumkeller_, Sep 21 2013
%H T. D. Noe, <a href="/A038610/b038610.txt">Table of n, a(n) for n=1..200</a>
%F a(n) = e^[Sum_{k=1..n} (1-floor(n^k/k)+floor((n^k -1)/k))*Mangoldt(k)] where Mangoldt is the Mangoldt function. - _Anthony Browne_, Jun 16 2016
%e Since 1, 5, 7, and 11 are relatively prime to 12, a(12) = LCM(1,5,7,11) = 385.
%p A038610 := n -> ilcm(op(select(k->igcd(n,k)=1,[$1..n]))); # _Peter Luschny_, Jun 25 2011
%t Table[ LCM@@ Flatten[ Position[ GCD[ n, # ]& /@ Range[ n ], 1 ] ], {n, 32} ]
%t Join[{1},Table[LCM@@Select[Range[n-1],CoprimeQ[#,n]&],{n,2,40}]] (* _Harvey P. Dale_, Mar 05 2016 *)
%o (PARI) a(n) = local(r); r=1;for(i=1,n-1,if(gcd(i,n)==1,r=lcm(r,i)));r \\ _Franklin T. Adams-Watters_, Apr 01 2008
%o (Haskell)
%o a038610 = foldl lcm 1 . a038566_row
%o -- _Reinhard Zumkeller_, Sep 21 2013, Oct 04 2011
%Y Cf. A034699, A000005.
%K nonn,nice
%O 1,3
%A _Wouter Meeussen_
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