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A087081 Sum of the elements in the coprime subsets of the integers 1 to n. 4
0, 1, 6, 24, 48, 156, 192, 580, 836, 1444, 1660, 4596, 4980, 13184, 14768, 17308, 21756, 55888, 58768, 146416, 157552, 181008, 196304, 481664, 500096, 765648, 825152, 1073920, 1148288, 2745728, 2768768, 6505728, 7453952, 8233792, 8736960, 9984832, 10208064 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

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

REFERENCES

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

LINKS

Fausto A. C. Cariboni, Table of n, a(n) for n = 0..120

EXAMPLE

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.

CROSSREFS

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.

Sequence in context: A120572 A000056 A083170 * A089973 A277014 A033581

Adjacent sequences:  A087078 A087079 A087080 * A087082 A087083 A087084

KEYWORD

nonn

AUTHOR

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

EXTENSIONS

Terms a(35) and beyond from Fausto A. C. Cariboni, Oct 20 2020

STATUS

approved

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Last modified March 3 12:59 EST 2021. Contains 341762 sequences. (Running on oeis4.)