%I #6 Jul 30 2024 05:15:28
%S 3,5,18,90,552,3960,32400,297360,3024000,33747840,410054400,
%T 5388768000,76161254400,1151998848000,18568976025600,317764871424000,
%U 5753767219200000,109907415281664000,2208818928476160000,46590073456582656000,1029117549458718720000
%N a(n) = n! - 2(n-1)! + 3(n-2)!.
%F D-finite with recurrence a(n) +(-n-2)*a(n-1) +(2*n-1)*a(n-2) +3*(-n+4)*a(n-3)=0. - _R. J. Mathar_, Jul 30 2024
%p A374649 := proc(n)
%p n!-2*(n-1)!+3*(n-2)! ;
%p end proc:
%p seq(A374649(n),n=2..50) ; # _R. J. Mathar_, Jul 30 2024
%t Table[n! - 2 (n - 1)! + 3 (n - 2)!, {n, 2, 25}]
%Y Cf. A000142, A374650.
%K nonn
%O 2,1
%A _Clark Kimberling_, Jul 25 2024