A103297 Number of different lengths that perfect rulers with n segments can have.

1, 1, 2, 3, 3, 4, 4, 6, 6, 7, 7, 7, 8, 10, 11, 11, 11, 11, 11, 13, 14, 15, 15, 16, 14, 19

Offset

0,3

Comments

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

Links

Table of n, a(n) for n=0..25.

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) = A004137(n+1) - A004137(n) for n>= 1.

Example

a(5)=4 because a perfect ruler with 5 segments may have the length 10, 11, 12 or 13.

Crossrefs

Cf. A103298.

Sequence in context: A318283 A105677 A230476 * A274017 A267597 A238221

Adjacent sequences: A103294 A103295 A103296 * A103298 A103299 A103300

Keyword

nonn,hard

Author

Peter Luschny, Feb 28 2005

Extensions

Term a(19) corrected and terms a(20)-a(25) added by Fabian Schwartau, Yannic Schröder, Lars Wolf, Joerg Schoebel, Feb 23 2021

Status

approved