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A157650 Number of minimum geometric construction etches with compass of fixed opening and straight-edge to find the centroid of n points. 0
0, 4, 9, 12, 19, 21, 28, 28, 36, 38, 46, 45 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

Archimedes, On the equilibrium of planes, 287 BC-212 BC (Proposition 4, Book I).

Jason E. Shields, Archimedes Lemma Variation, February 13, 2009 (unpublished).

LINKS

Table of n, a(n) for n=1..12.

Tom A. Apostol and Mamikon A. Mnastakanian, Finding Centroids The Easy Way, Math Horizons, September (2000), 7-12.

EXAMPLE

For n=4, the minimum number of geometric etches to find the centroid of 4 points is 12 using a compass of fixed opening.

CROSSREFS

Sequence in context: A312865 A181023 A084789 * A312866 A312867 A312868

Adjacent sequences:  A157647 A157648 A157649 * A157651 A157652 A157653

KEYWORD

nonn,more

AUTHOR

Jason E. Shields, Mar 03 2009, Mar 13 2009

STATUS

approved

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Last modified September 23 03:04 EDT 2020. Contains 337291 sequences. (Running on oeis4.)