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A378447 Difference between {the number of distinct sums of distinct divisors of n} and {the number of distinct sums of distinct proper divisors of n}.

%I A378447 #7 Nov 29 2024 12:23:14
%S A378447 1,2,2,4,2,6,2,8,4,8,2,12,2,8,8,16,2,18,2,20,8,8,2,24,4,8,8,28,2,30,2,
%T A378447 32,8,8,8,36,2,8,8,40,2,42,2,32,28,8,2,48,4,32,8,32,2,54,8,56,8,8,2,
%U A378447 60,2,8,30,64,8,66,2,32,8,70,2,72,2,8,32,32,8,78,2,80,16,8,2,84,8,8,8,88,2,90,8,32,8,8,8
%N A378447 Difference between {the number of distinct sums of distinct divisors of n} and {the number of distinct sums of distinct proper divisors of n}.
%H A378447 Antti Karttunen, <a href="/A378447/b378447.txt">Table of n, a(n) for n = 1..65537</a>
%F A378447 a(n) = A119347(n) - A193279(n).
%o A378447 (PARI) A378447(n) = (A119347(n) - A193279(n));
%o A378447 (PARI) A378447(n) = { my(c1=[0],c2=[0]); fordiv(n,d, c1 = Set(concat(c1,vector(#c1,i,c1[i]+d))); if(d<n, c2 = Set(concat(c2,vector(#c2,i,c2[i]+d))))); (#c1-#c2); }; \\ (see A119347 and A193279)
%Y A378447 Cf. A119347, A193279.
%K A378447 nonn
%O A378447 1,2
%A A378447 _Antti Karttunen_, Nov 29 2024