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 A087077 Total number of elements in all primitive subsets of the integers 1 to n. 2
 0, 1, 2, 5, 8, 21, 29, 73, 105, 193, 288, 677, 853, 1957, 2961, 4913, 6809, 15145, 19605, 43105, 57889, 98849, 151457, 327505, 397825, 784945, 1201189, 2009229, 2772729, 5901185, 7364945, 15609825, 21206049, 36440033 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS A primitive set has no element that divides another element in the same set. REFERENCES R. K. Guy, Unsolved Problems in Number Theory, Springer-Verlag, New York, (1994). LINKS Eric Weisstein's World of Mathematics, Primitive Sequence. EXAMPLE 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 CROSSREFS 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 Sequence in context: A107384 A205596 A092446 * A200276 A168081 A340399 Adjacent sequences:  A087074 A087075 A087076 * A087078 A087079 A087080 KEYWORD more,nonn AUTHOR Alan Sutcliffe (alansut(AT)ntlworld.com), Aug 10 2003 STATUS approved

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Last modified May 8 02:26 EDT 2021. Contains 343652 sequences. (Running on oeis4.)