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Search: id:A087078
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| A087078 |
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Sum of the elements in the primitive subsets of the integers 1 to n. |
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+0
3
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| 0, 1, 3, 11, 22, 73, 115, 341, 545, 1141, 1864, 4849, 6505, 16285, 26245, 47093, 68981, 163937, 221957, 517937, 726737, 1312865, 2093745, 4753105, 5953777, 12335601, 19516365, 34112821, 48603289, 107522689, 137759953, 302797921, 422868865
(list; graph; listen)
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OFFSET
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0,3
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COMMENT
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A primitive set has no element that divides another element in the same set.
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REFERENCES
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R. K. Guy, Unsolved Problems in Number Theory, Springer-Verlag, New York, (1994).
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LINKS
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Eric Weisstein's World of Mathematics, Primitive Sequence.
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EXAMPLE
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a(4)=22 since the primitive subsets of (1,2,3,4) are ( ) (1) (2) (3) (4) (2,3) (3,4) and the sum of the elements in these subsets is 22.
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CROSSREFS
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A051026 gives the number of primitive subsets. A087077 gives the number of elements in the primitive subsets. A087081 gives the sum of the elements in the coprime subsets.
Sequence in context: A129215 A139593 A121471 this_sequence A141226 A049491 A000355
Adjacent sequences: A087075 A087076 A087077 this_sequence A087079 A087080 A087081
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KEYWORD
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nonn
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AUTHOR
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Alan Sutcliffe (alansut(AT)ntlworld.com), Aug 12 2003
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