%I #22 Mar 12 2018 03:50:31

%S 0,1,4,18,48,150,180,980,2240,5670,6300,30492,11088,156156,168168,

%T 257400,1647360,3719430,3938220,17551820,18475600,81477396,85357272,

%U 373173528,389398464,1690097500,1757701400,7582037400,3931426800,33738060600

%N a(n) = lcm(n^2, swinging_factorial(n)).

%H Vincenzo Librandi, <a href="/A181860/b181860.txt">Table of n, a(n) for n = 0..1000</a>

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

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

%t 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 *)

%o (PARI) a(n) = lcm(n^2, n!/(n\2)!^2); \\ _Michel Marcus_, Mar 06 2018

%Y Cf. A000290, A056040, A170825, A181861.

%K nonn

%O 0,3

%A _Peter Luschny_, Nov 21 2010

%E a(26)-a(29) from _Vincenzo Librandi_, Mar 05 2018