n-th derivative of sech(x)^tanh(x) at x=0.

Terms

a(0) =1a(1) =0a(2) =0a(3) =-3a(4) =0a(5) =30a(6) =90a(7) =-588a(8) =-5040a(9) =11400a(10) =325080a(11) =336072a(12) =-25237080a(13) =-126955920a(14) =2273150880a(15) =25210740552a(16) =-217110741120