tan(arctanh(x)*cos(x))=x+1/3!*x^3+5/5!*x^5+509/7!*x^7+44393/9!*x^9...

A012741

tan(arctanh(x)*cos(x))=x+1/3!*x^3+5/5!*x^5+509/7!*x^7+44393/9!*x^9...

Terms

    a(0) =1a(1) =1a(2) =5a(3) =509a(4) =44393a(5) =4436441a(6) =630529965a(7) =126873147413

External references