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 A325313 a(n) = A048250(n) - n, where A048250(n) is the sum of squarefree divisors of n. 17

%I

%S 0,1,1,-1,1,6,1,-5,-5,8,1,0,1,10,9,-13,1,-6,1,-2,11,14,1,-12,-19,16,

%T -23,-4,1,42,1,-29,15,20,13,-24,1,22,17,-22,1,54,1,-8,-21,26,1,-36,

%U -41,-32,21,-10,1,-42,17,-32,23,32,1,12,1,34,-31,-61,19,78,1,-14,27,74,1,-60,1,40,-51,-16,19,90,1,-62,-77,44,1,12,23,46

%N a(n) = A048250(n) - n, where A048250(n) is the sum of squarefree divisors of n.

%H Antti Karttunen, <a href="/A325313/b325313.txt">Table of n, a(n) for n = 1..16384</a>

%H Antti Karttunen, <a href="/A325313/a325313.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%F a(n) = A048250(n) - n.

%F a(n) = A325314(n) - A033879(n).

%F a(A228058(n)) = -A325319(n).

%t Array[DivisorSum[#, # &, SquareFreeQ] - # &, 86] (* _Michael De Vlieger_, Apr 21 2019 *)

%o (PARI)

%o A048250(n) = factorback(apply(p -> p+1,factor(n)[,1]));

%o A325313(n) = (A048250(n) - n);

%Y Cf. A033879, A048250, A126795, A228058, A325314, A325315, A325319, A325320.

%K sign

%O 1,6

%A _Antti Karttunen_, Apr 21 2019

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Last modified May 6 15:28 EDT 2021. Contains 343586 sequences. (Running on oeis4.)