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A117214 a(n) = (A117213(n))/(n-th squarefree positive integer). 3

%I

%S 1,1,2,6,1,30,3,210,2310,15,2,30030,510510,10,105,9699690,1155,

%T 223092870,1,6469693230,70,15015,6,200560490130,255255,770,

%U 7420738134810,5,304250263527210,4849845,13082761331670030,10010

%N a(n) = (A117213(n))/(n-th squarefree positive integer).

%C Product of all primes up to greatest prime factor of n-th squarefree number that do not divide the n-th squarefree number. - _Franklin T. Adams-Watters_, Oct 09 2006

%H Reinhard Zumkeller, <a href="/A117214/b117214.txt">Table of n, a(n) for n = 1..1000</a>

%e 10 is the 7th squarefree integer. And 2*3*5 = 30 is the smallest primorial number divisible by 10 = 2*5. So a(7) = 30/10 = 3.

%t Product[Prime@ i, {i, PrimePi@ FactorInteger[#][[-1, 1]]}]/# & /@ Select[Range@ 52, SquareFreeQ] (* _Michael De Vlieger_, Sep 30 2017 *)

%o (Haskell)

%o a117214 n = product $

%o filter ((> 0) . (mod m)) $ takeWhile (< a006530 m) a000040_list

%o where m = a005117 n

%o -- _Reinhard Zumkeller_, Jan 14 2012

%Y Cf. A117213.

%Y Cf. A006530, A005117, A073482, A073483.

%K nonn

%O 1,3

%A _Leroy Quet_, Mar 03 2006

%E More terms from _Franklin T. Adams-Watters_, Oct 09 2006

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Last modified June 13 20:25 EDT 2021. Contains 345009 sequences. (Running on oeis4.)