A012418 sec(arctan(x)*exp(x))=1+1/2!*x^2+6/3!*x^3+21/4!*x^4+100/5!*x^5...

1, 0, 1, 6, 21, 100, 1005, 9170, 73353, 794952, 11042745, 144625118, 1936131549, 31475441452, 562265168101, 9960214270890, 187956163443857, 3970728871687824, 88040662078595313, 1994667867977462454