Expansion of sin(tan(x))*x/2.A024226Expansion of sin(tan(x))*x/2.Terms a(0) =0a(1) =1a(2) =2a(3) =-9a(4) =-1100a(5) =-75075a(6) =-5809002a(7) =-539002541a(8) =-59464355288External referencesoeis: A024226