%I #13 Aug 13 2017 17:40:45
%S 1,2,8,24,48,384,1152,2304,9216,46080,414720,829440,13271040,79626240,
%T 318504960,637009920,1911029760,15288238080,107017666560,535088332800,
%U 1070176665600,9631589990400,38526359961600,77052719923200
%N Product of all composite numbers from 1 to the n-th nonprime number divided by product of all the prime divisors of each of those composite numbers which exceed the previously stated value.
%C More precisely the denominator equals the product of the largest squarefree divisors of composite numbers up to n.
%F a(1)=1, a(n) = a(n-1)*n/(n's prime factors).
%e a(4) = (1*4*6*8*9)/((2)*(2*3)*(2)*(3)) = 24.
%p A084744 := proc(n) sort(convert(convert(A085056(n),set),list)) end: # _Peter Luschny_, Jun 29 2009
%t PrimeFactors[ n_Integer ] := Flatten[ Table[ # [ [ 1 ] ], {1} ] & /@ FactorInteger[ n ] ]; a[ 1 ] := 1; a[ n_ ] := a[ n ] = a[ n - 1 ]*n / Times @@ PrimeFactors[ n ]; Union[ Table[ a[ n ], {n, 1, 63} ]
%Y Cf. A084056.
%K nonn
%O 1,2
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 26 2003
%E Edited and extended by _Robert G. Wilson v_, Jun 27 2003
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