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%I #15 Jun 27 2022 10:50:24
%S 0,1,2,5,8,21,29,73,105,193,288,677,853,1957,2961,4913,6809,15145,
%T 19605,43105,57889,98849,151457,327505,397825,784945,1201189,2009229,
%U 2772729,5901185,7364945,15609825,21206049,36440033,55602033,105010513,127336513,267374561
%N Total number of elements in all primitive subsets of the integers 1 to n.
%C A primitive set has no element that divides another element in the same set.
%D R. K. Guy, Unsolved Problems in Number Theory, Springer-Verlag, New York, (1994).
%H Fausto A. C. Cariboni, <a href="/A087077/b087077.txt">Table of n, a(n) for n = 0..75</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimitiveSequence.html">Primitive Sequence</a>.
%F a(n) = Sum_{k=1..ceiling(n/2)} k * A355145(n,k). - _Alois P. Heinz_, Jun 27 2022
%e a(4)=8 since the primitive subsets of (1,2,3,4) are ( ) (1) (2) (3) (4) (2,3) (3,4) and these contain eight elements
%Y A051026 gives the number of primitive subsets. A087078 gives the sum of the elements of the primitive subsets. A087080 gives the number elements in the coprime subsets.
%Y Cf. A355145.
%K nonn
%O 0,3
%A Alan Sutcliffe (alansut(AT)ntlworld.com), Aug 10 2003
%E Terms a(34)-a(37) from _Fausto A. C. Cariboni_, Feb 02 2022