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%I #8 May 19 2022 09:21:22
%S 1,2,3,2,5,6,7,2,3,10,11,12,13,14,15,2,17,18,19,20,21,22,23,24,5,26,3,
%T 28,29,30,31,2,33,34,35,6,37,38,39,40,41,42,43,44,45,46,47,48,7,50,51,
%U 52,53,54,55,56,57,58,59,60,61,62,63,2,65,66,67,68,69,70,71,12,73,74,75,76,77,78,79,80,3,82,83
%N A weakening function. a(n) = n / A007947(n)^(A051904(n) - 1) where A007947 is squarefree kernel and A051904 is minimum prime exponent.
%C This function takes powerful numbers (A001694) to weak numbers (A052485) and leaves weak numbers unchanged.
%C First differs from A052410 at a(72) = 12, A052410(72) = 72.
%H Antti Karttunen, <a href="/A304776/b304776.txt">Table of n, a(n) for n = 1..20000</a>
%F a(n) = n / A354090(n). - _Antti Karttunen_, May 19 2022
%t spr[n_]:=Module[{f,m},f=FactorInteger[n];m=Min[Last/@f];n/Times@@First/@f^(m-1)];
%t Array[spr,100]
%o (PARI)
%o A007947(n) = factorback(factorint(n)[, 1]);
%o A051904(n) = if((1==n),0,vecmin(factor(n)[, 2]));
%o A304776(n) = (n/(A007947(n)^(A051904(n)-1))); \\ _Antti Karttunen_, May 19 2022
%Y Cf. A001597, A001694, A005117, A007947, A013929, A047966, A051903, A051904, A052485, A062759, A066636, A066638, A072774, A304768, A354090.
%K nonn
%O 1,2
%A _Gus Wiseman_, May 18 2018
%E Data section extended up to a(83) by _Antti Karttunen_, May 19 2022
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