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 A073482 Largest prime factor of the n-th squarefree number. 10
 1, 2, 3, 5, 3, 7, 5, 11, 13, 7, 5, 17, 19, 7, 11, 23, 13, 29, 5, 31, 11, 17, 7, 37, 19, 13, 41, 7, 43, 23, 47, 17, 53, 11, 19, 29, 59, 61, 31, 13, 11, 67, 23, 7, 71, 73, 37, 11, 13, 79, 41, 83, 17, 43, 29, 89, 13, 31, 47, 19, 97, 101, 17, 103, 7, 53, 107, 109, 11, 37, 113, 19, 23, 59, 17, 61, 41 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) = A006530(A005117(n)). a(n) = A265668(n, A001221(n)). - Reinhard Zumkeller, Dec 13 2015 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 MAPLE issquarefree := proc(n::integer) local nf, ifa, lar; nf := op(2, ifactors(n)); for ifa from 1 to nops(nf) do lar := op(1, op(ifa, nf)); if op(2, op(ifa, nf)) >= 2 then RETURN(0); fi; od : RETURN(lar); end: printf("1, "); for n from 2 to 100 do lfa := issquarefree(n); if lfa > 0 then printf("%a, ", lfa); fi; od : # R. J. Mathar, Apr 02 2006 MATHEMATICA FactorInteger[#][[-1, 1]]& /@ Select[Range[100], SquareFreeQ] (* Jean-François Alcover, Feb 01 2018 *) PROG (Haskell) a073482 = a006530 . a005117  -- Reinhard Zumkeller, Feb 04 2012 (PARI) do(x)=my(v=List([1])); forfactored(n=2, x\1, if(vecmax(n[2][, 2])==1, listput(v, vecmax(n[2][, 1])))); Vec(v) \\ Charles R Greathouse IV, Nov 05 2017 CROSSREFS Cf. A073481, A001221, A005117, A006530, A265668. Sequence in context: A092386 A117369 A117366 * A318411 A225680 A107685 Adjacent sequences:  A073479 A073480 A073481 * A073483 A073484 A073485 KEYWORD nonn AUTHOR Reinhard Zumkeller, Aug 03 2002 EXTENSIONS More terms from Jason Earls, Aug 06 2002 STATUS approved

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Last modified October 18 00:09 EDT 2019. Contains 328135 sequences. (Running on oeis4.)