Expansion of e.g.f. log(1+log(1+x)/cos(x)).

Terms

a(0) =0a(1) =1a(2) =-2a(3) =10a(4) =-53a(5) =393a(6) =-3469a(7) =36923a(8) =-455034a(9) =6408445a(10) =-101394621a(11) =1782112451a(12) =-34444229280a(13) =726178939315