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A325814 a(n) = n - A048146(n), where A048146 is the sum of non-unitary divisors of n.

%I A325814 #16 Feb 22 2024 02:18:34
%S A325814 1,2,3,2,5,6,7,2,6,10,11,4,13,14,15,2,17,9,19,8,21,22,23,0,20,26,15,
%T A325814 12,29,30,31,2,33,34,35,-5,37,38,39,4,41,42,43,20,27,46,47,-8,42,35,
%U A325814 51,24,53,18,55,8,57,58,59,12,61,62,39,2,65,66,67,32,69,70,71,-33,73,74,55,36,77,78,79,-4,42,82,83,20
%N A325814 a(n) = n - A048146(n), where A048146 is the sum of non-unitary divisors of n.
%H A325814 Antti Karttunen, <a href="/A325814/b325814.txt">Table of n, a(n) for n = 1..20000</a>
%F A325814 a(n) = n - A048146(n).
%F A325814 a(n) = A033879(n) + A034460(n).
%F A325814 a(A228058(n)) = A325824(n).
%F A325814 Sum_{k=1..n} a(k) ~ c * n^2, where c = 1/2 - zeta(2) * (1 - 1/zeta(3)) / 2 = 0.3617493553... . - _Amiram Eldar_, Feb 22 2024
%t A325814 Table[n - DivisorSum[n, # &, ! CoprimeQ[#, n/#] &], {n, 84}] (* _Michael De Vlieger_, May 27 2019 *)
%o A325814 (PARI)
%o A325814 A048146(n) = (sigma(n)-A034448(n));
%o A325814 A325814(n) = (n-A048146(n));
%Y A325814 Cf. A000203, A033879, A034448, A034460, A048146, A064591 (positions of zeros), A228058, A325812, A325813, A325824.
%Y A325814 Cf. also A325314.
%Y A325814 Cf. A002117, A013661.
%K A325814 sign
%O A325814 1,2
%A A325814 _Antti Karttunen_, May 23 2019