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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
OFFSET
0,3
LINKS
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-François Alcover, Jun 28 2013 *)
PROG
(PARI) a(n) = lcm(n^2, n!/(n\2)!^2); \\ Michel Marcus, Mar 06 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Nov 21 2010
EXTENSIONS
a(26)-a(29) from Vincenzo Librandi, Mar 05 2018
STATUS
approved