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A110901
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Product_{k=1..n} (A013929(k)), the product of the first n positive integers that are each divisible by at least one square >= 4.
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0
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4, 32, 288, 3456, 55296, 995328, 19906560, 477757440, 11943936000, 322486272000, 9029615616000, 288947699712000, 10402117189632000, 416084687585280000, 18307726253752320000, 823847681418854400000, 39544688708105011200000
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OFFSET
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1,1
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LINKS
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EXAMPLE
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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.
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MATHEMATICA
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Rest[ FoldList[ Times, 1, Select[ Range[2, 48], (Union[Last /@ FactorInteger[ # ]][[ -1]] > 1) == True &]]] (* Robert G. Wilson v *)
FoldList[Times, Select[Range[50], !SquareFreeQ[#]&]] (* Harvey P. Dale, Dec 31 2022 *)
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PROG
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(PARI) a=1; for(n=1, 48, if(!issquarefree(n), print1(a=a*n, ", ")))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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