A218537 - OEIS

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A218537

Minimum number of unit length rods needed to construct a rigid regular n-gon.

3, 19, 31, 11, 35, 31, 51, 55, 155, 49

(list; graph; refs; listen; history; text; internal format)

OFFSET

3,1

COMMENTS

The terms in this sequence are the best known solutions and they may not be optimal.

LINKS

Table of n, a(n) for n=3..12.

Erich Friedman, Problem of the Month (January 2000)

Ed Pegg, Is this braced heptagon a rigid graph?, Mathematics Stack Exchange, December 2020.

Kaylee Weatherspoon, Structure of Extremal Unit Distance Graphs, Senior Thesis, Honors College, Univ. S. Carolina - Columbia (2023). See p. 28.

CROSSREFS

Sequence in context: A250027 A339545 A102978 * A236969 A222590 A107165

Adjacent sequences: A218534 A218535 A218536 * A218538 A218539 A218540

KEYWORD

hard,more,nonn

AUTHOR

Arkadiusz Wesolowski, Nov 01 2012

EXTENSIONS

a(7) updated according to Jeremy Tan's answer to Ed Pegg's question by Andrey Zabolotskiy, Dec 21 2020

Name clarified by Pontus von Brömssen, May 07 2023

STATUS

approved