A012520 arctan(sinh(x)*exp(x))=x+2/2!*x^2+2/3!*x^3-16/4!*x^4-160/5!*x^5...

1, 2, 2, -16, -160, -688, 3152, 99584, 992000, 31232, -190094848, -3600265216, -20655831040, 737829988352, 25775848957952, 333499542339584, -4040309414625280, -311707129046499328, -7000770202915176448