%I A060841
%S A060841 1,4,18,144,900,16200,132300,2116800,28576800,714420000,8644482000,
%T A060841 311201352000,4382752374000,143169910884000,4026653743612500,
%U A060841 128852919795600000,2327405863808025000,125679916645633350000
%N A060841 1/det(M) where M is the n X n matrix with M[i,j]= 1/lcm(i,j).
%C A060841 The value is not always an integer! For example, a(35) = 5029296746186844716050163189085401314000634765625/
               2 . [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 13 2009]
%F A060841 a(n) = (n!)^2 / (phi(1)*phi(2)*...*phi(n)) = (n!)^2 / A001088(n)
%e A060841 a(2) = 4 because the matrix M is: [1,1/2; 1/2,1/2] and det(M) = 1/4
%Y A060841 A001088, A000010, A060238.
%Y A060841 Sequence in context: A065857 A156445 A143992 this_sequence A059837 A054759 
               A007153
%Y A060841 Adjacent sequences: A060838 A060839 A060840 this_sequence A060842 A060843 
               A060844
%K A060841 nonn,easy
%O A060841 1,2
%A A060841 Noam Katz (noamkj(AT)hotmail.com), May 02 2001
%E A060841 More terms from Reiner Martin (reinermartin(AT)hotmail.com), May 17 2001