arctanh(sec(x)*tanh(x))=x+3/3!*x^3+65/5!*x^5+2723/7!*x^7...

A012837

arctanh(sec(x)*tanh(x))=x+3/3!*x^3+65/5!*x^5+2723/7!*x^7...

Terms

    a(0) =1a(1) =3a(2) =65a(3) =2723a(4) =226785a(5) =29857443a(6) =5785047905

External references