A103299 - OEIS

A103299

Number of optimal rulers with n segments (n>=0).

1, 1, 2, 2, 4, 6, 12, 4, 6, 2, 2, 4, 12, 4, 2, 2, 2, 2, 4, 2, 2, 2, 2, 2, 4

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OFFSET

0,3

COMMENTS

For definitions, references and links related to complete rulers see A103294.

LINKS

Table of n, a(n) for n=0..24.

F. Schwartau, Y. Schröder, L. Wolf and J. Schoebel, MRLA search results and source code, Nov 6 2020.

F. Schwartau, Y. Schröder, L. Wolf and J. Schoebel, Large Minimum Redundancy Linear Arrays: Systematic Search of Perfect and Optimal Rulers Exploiting Parallel Processing, IEEE Open Journal of Antennas and Propagation, 2 (2021), 79-85.

Index entries for sequences related to perfect rulers.

FORMULA

a(n) = A103300(A004137(n+1)).

EXAMPLE

a(5)=6 counts the optimal rulers with 5 segments, {[0,1,6,9,11,13], [0,2,4,7,12,13], [0,1,4,5,11,13], [0,2,8,9,12,13], [0,1,2,6,10,13], [0,3,7,11,12,13]}.

CROSSREFS

Cf. A103296 (Complete rulers with n segments), A103301 (Perfect rulers with n segments).

Sequence in context: A000672 A129860 A115868 * A278246 A195204 A318847

Adjacent sequences: A103296 A103297 A103298 * A103300 A103301 A103302

KEYWORD

nonn,hard,more

AUTHOR

Peter Luschny, Feb 28 2005

EXTENSIONS

Terms a(20)-a(24) proved by exhaustive search by Fabian Schwartau, Yannic Schröder, Lars Wolf, Joerg Schoebel, Feb 22 2021

STATUS

approved