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 A073483 For the n-th squarefree number: the product of all primes greater than its smallest factor and less than its largest factor and not dividing it. 6
 1, 1, 1, 1, 1, 1, 3, 1, 1, 15, 1, 1, 1, 5, 105, 1, 1155, 1, 1, 1, 35, 15015, 1, 1, 255255, 385, 1, 5, 1, 4849845, 1, 5005, 1, 7, 85085, 111546435, 1, 1, 3234846615, 77, 35, 1, 1616615, 3, 1, 1, 100280245065, 1, 385, 1, 3710369067405, 1, 1001 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 COMMENTS a(n)=1 iff A073484(n)=0; a(A000040(n))=1, a(A006094(n))=1, a(A002110(n))=1. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 FORMULA a(n) = A002110(A073482(n))/(A005117(n)*A002110(A073481(n))). EXAMPLE The 69th squarefree number is 110=2*5*11, primes between 2 and 11, not dividing 110, are 3 and 7, therefore a(69)=21. MATHEMATICA ppg[n_]:=Module[{f=Transpose[FactorInteger[n]][[1]]}, Times@@Select[Prime[ Range[PrimePi[First[f]]+1, PrimePi[Last[f]]-1]], !MemberQ[f, #]&]]; ppg/@ Select[ Range[100], SquareFreeQ] (* Harvey P. Dale, Jan 16 2013 *) PROG (Haskell) a073483 n = product \$ filter ((> 0) . (mod m)) \$    dropWhile (<= a020639 m) \$ takeWhile (<= a006530 m) a000040_list    where m = a005117 n -- Reinhard Zumkeller, Jan 15 2012 CROSSREFS Cf. A005117, A000040, A073484, A117214. Sequence in context: A156869 A153090 A203002 * A006956 A072285 A144269 Adjacent sequences:  A073480 A073481 A073482 * A073484 A073485 A073486 KEYWORD nonn,nice AUTHOR Reinhard Zumkeller, Aug 03 2002 EXTENSIONS a(44) and a(49) corrected by Reinhard Zumkeller, Jan 14 2012 Definition clarified by Harvey P. Dale, Jan 16 2013 STATUS approved

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Last modified June 18 17:20 EDT 2021. Contains 345120 sequences. (Running on oeis4.)