Expansion of e.g.f. log(sec(x) + arctan(x)).

Terms

a(0) =0a(1) =1a(2) =0a(3) =-3a(4) =16a(5) =-27a(6) =-48a(7) =777a(8) =-5504a(9) =48905a(10) =-149120a(11) =-4320107a(12) =76593152a(13) =-424303635a(14) =-2866784256a(15) =77237001761