A180402 a(n) = lcm(1,...,Fibonacci(n)).

1, 1, 2, 6, 60, 840, 360360, 232792560, 144403552893600, 164249358725037825439200, 718766754945489455304472257065075294400, 33312720618553145840562713089120360606823375590405920630576000

Offset: 1

Author

Vaclav Kotesovec, Sep 02 2010

Keywords

• nonn

Comments

Also least period for number of ways of placing k non-attacking queens on an n X n chessboard. [conjectured by Kotesovec; proved for n <= 5. - Thomas Zaslavsky, Jun 24 2018]

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..17
• Christopher R. H. Hanusa, T. Zaslavsky, S. Chaiken, A q-Queens Problem. IV. Queens, Bishops, Nightriders (and Rooks), arXiv preprint arXiv:1609.00853 [math.CO], 2016. See Table 8.1.
• V. Kotesovec, Non-attacking chess pieces, 6ed, p.31, 2013

Crossrefs

Cf. A178717, A178721, A078491, A218492, A035105, A062954.

Programs

Maple

a:= n-> ilcm($1..(<<0|1>, <1|1>>^n)[1,2]):
seq(a(n), n=1..14);  # Alois P. Heinz, Aug 12 2017

Mathematica

Table[Apply[LCM, Range[Fibonacci[k]]], {k, 1, 10}]
Array[LCM @@ Range@Fibonacci@# &, 12] (* Robert G. Wilson v, Sep 05 2010 *)

PARI

a(n) = lcm([1..fibonacci(n)]); \\ Michel Marcus, Jun 24 2018

Extensions

a(11) onwards from Robert G. Wilson v, Sep 05 2010