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A005410 a(n) = largest integer m such that every n-point interval order contains an m-point semiorder.
(Formerly M0435)
1
1, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 9, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Equivalently, a(n) is the largest integer m such that every n-point interval graph contains an m-point unit interval graph.

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=1..18.

P. C. Fishburn, Letter to N. J. A. Sloane, Jul 1980

Peter C. Fishburn, Maximum semiorders in interval orders, SIAM J. Algebraic Discrete Methods 2 (1981), no. 2, 127-135.

CROSSREFS

Sequence in context: A206916 A067086 A254531 * A120835 A091374 A266977

Adjacent sequences:  A005407 A005408 A005409 * A005411 A005412 A005413

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Better definition from N. J. A. Sloane, Mar 25 2014

STATUS

approved

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Last modified December 18 12:06 EST 2018. Contains 318229 sequences. (Running on oeis4.)