A293918 - OEIS

A293918

Number of linear chord diagrams having n chords and minimal chord length five.

1, 39, 796, 14296, 265103, 5317342, 116235247, 2760729582, 70870525294, 1956309944351, 57803029075220, 1820704829013410, 60915564036123607, 2157741151756229543, 80681075613289079236, 3176017007139110899224, 131302895736890434892224, 5688257327967598478393309

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OFFSET

5,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 5..404

FORMULA

a(n) ~ (exp(-4) - exp(-5)) * 2^(n + 1/2) * n^n / exp(n). - Vaclav Kotesovec, Oct 25 2017

CROSSREFS

Column k=5 of A293881.

Sequence in context: A232067 A247222 A268983 * A264458 A004330 A069418

Adjacent sequences: A293915 A293916 A293917 * A293919 A293920 A293921

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Oct 19 2017

STATUS

approved