cp's OEIS Frontend

A326045 a(n) is the sum of divisors of n, minus the largest square dividing that sum, minus n: a(n) = sigma(n) - A008833(sigma(n)) - n.

%I A326045 #5 Jun 05 2019 21:53:36
%S A326045 -1,0,-3,2,0,2,-3,6,3,-1,-3,12,0,6,5,14,-8,20,-3,21,-5,-22,-3,32,5,15,
%T A326045 9,24,0,6,-15,22,-1,11,-3,54,0,18,13,41,0,38,-3,36,32,-10,-15,72,7,42,
%U A326045 -15,-3,-8,62,-19,60,7,23,-3,104,0,18,37,62,15,-66,-3,49,11,-70,-35,122,0,39,45,60,3,86,-15,105,-81,35,-3
%N A326045 a(n) is the sum of divisors of n, minus the largest square dividing that sum, minus n: a(n) = sigma(n) - A008833(sigma(n)) - n.
%H A326045 Antti Karttunen, <a href="/A326045/b326045.txt">Table of n, a(n) for n = 1..20000</a>
%H A326045 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A326045 a(n) = A326040(n) - n = sigma(n) - A008833(sigma(n)) - n.
%o A326045 (PARI)
%o A326045 A008833(n) = (n/core(n));
%o A326045 A326039(n) = A008833(sigma(n));
%o A326045 A326040(n) = (sigma(n)-A008833(sigma(n)));
%o A326045 A326045(n) = (A326040(n)-n);
%Y A326045 Cf. A000203, A008833, A326039, A326040, A326044, A326046.
%K A326045 sign
%O A326045 1,3
%A A326045 _Antti Karttunen_, Jun 05 2019