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A110901 Product_{k=1..n} (A013929(k)), the product of the first n positive integers that are each divisible by at least one square >= 4. 0

%I

%S 4,32,288,3456,55296,995328,19906560,477757440,11943936000,

%T 322486272000,9029615616000,288947699712000,10402117189632000,

%U 416084687585280000,18307726253752320000,823847681418854400000,39544688708105011200000

%N Product_{k=1..n} (A013929(k)), the product of the first n positive integers that are each divisible by at least one square >= 4.

%e Since 4, 8, 9 and 12 are the first 4 nonsquarefree positive integers, the fourth term of the sequence is 4*8*9*12 = 3456.

%t Rest[ FoldList[ Times, 1, Select[ Range[2, 48], (Union[Last /@ FactorInteger[ # ]][[ -1]] > 1) == True &]]] (* _Robert G. Wilson v_ *)

%o (PARI) a=1;for(n=1,48,if(!issquarefree(n),print1(a=a*n,",")))

%Y Cf. A013929, A111059.

%K nonn

%O 1,1

%A _Leroy Quet_, Oct 09 2005

%E More terms from _Klaus Brockhaus_ and _Robert G. Wilson v_, Oct 11 2005

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Last modified February 27 19:10 EST 2020. Contains 332308 sequences. (Running on oeis4.)