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A181860 a(n) = lcm(n^2, swinging_factorial(n)). 5
0, 1, 4, 18, 48, 150, 180, 980, 2240, 5670, 6300, 30492, 11088, 156156, 168168, 257400, 1647360, 3719430, 3938220, 17551820, 18475600, 81477396, 85357272, 373173528, 389398464, 1690097500, 1757701400, 7582037400, 3931426800, 33738060600 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = lcm(A000290(n), A056040(n)).

MAPLE

A181860 := n -> ilcm(n^2, n!/iquo(n, 2)!^2);

MATHEMATICA

Join[{0}, sf[n_]:=n!/Quotient[n, 2]!^2; a[n_]:=LCM[n^2, sf[n]]; Table[a[n], {n, 30}] ] (* Jean-Fran├žois Alcover, Jun 28 2013 *)

PROG

(PARI) a(n) = lcm(n^2, n!/(n\2)!^2); \\ Michel Marcus, Mar 06 2018

CROSSREFS

Cf. A000290, A056040, A170825, A181861.

Sequence in context: A045991 A228108 A259451 * A027271 A073991 A052642

Adjacent sequences:  A181857 A181858 A181859 * A181861 A181862 A181863

KEYWORD

nonn

AUTHOR

Peter Luschny, Nov 21 2010

EXTENSIONS

a(26)-a(29) from Vincenzo Librandi, Mar 05 2018

STATUS

approved

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Last modified March 29 17:23 EDT 2020. Contains 333116 sequences. (Running on oeis4.)