(-1)^(n+1)*n*A174276(n).

Terms

a(0) =0a(1) =2a(2) =-12a(3) =90a(4) =-280a(5) =1050a(6) =-13860a(7) =70070a(8) =-48048a(9) =4594590a(10) =-4618900a(11) =106696590a(12) =-382444920a(13) =966735770a(14) =-3123300180a(15) =97045398450a(16) =-97241449760