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Sum of the elements in the coprime subsets of the integers 1 to n.
4

%I #5 Oct 20 2020 14:56:12

%S 0,1,6,24,48,156,192,580,836,1444,1660,4596,4980,13184,14768,17308,

%T 21756,55888,58768,146416,157552,181008,196304,481664,500096,765648,

%U 825152,1073920,1148288,2745728,2768768,6505728,7453952,8233792,8736960,9984832,10208064

%N Sum of the elements in the coprime subsets of the integers 1 to n.

%C A coprime set of integers has (m,n)=1 for each pair of integers in the set.

%D Alan Sutcliffe, Divisors and Common Factors in Sets of Integers, awaiting publication.

%H Fausto A. C. Cariboni, <a href="/A087081/b087081.txt">Table of n, a(n) for n = 0..120</a>

%e a(4)=48 since the 12 coprime subsets of (1,2,3,4) are ( ) (1) (2) (3) (4) (1,2) (1,3) (1,4) (2,3) (3,4) (1,2,3) (1,3 4) and the sum of the elements is 48.

%Y A087078 gives the sum of the elements in the primitive subsets. A084422 gives the number coprime subsets. A087080 gives the number of elements in coprime subsets.

%K nonn

%O 0,3

%A Alan Sutcliffe (alansut(AT)ntlworld.com), Aug 12 2003

%E Terms a(35) and beyond from _Fausto A. C. Cariboni_, Oct 20 2020