E.g.f.: (1 + x) * exp(x) / (sec(x) + tan(x)).

Terms

a(0) =1a(1) =1a(2) =0a(3) =-1a(4) =-4a(5) =-5a(6) =-20a(7) =9a(8) =-208a(9) =855a(10) =-6180a(11) =41549a(12) =-321792a(13) =2651155a(14) =-23664420a(15) =225865769a(16) =-2301032256a(17) =24901626095a(18) =-285356879940