69177domain: NAppears in sequencestan(cosh(x)*arctan(x))=x+3/3!*x^3+45/5!*x^5+1071/7!*x^7+69177/9!*x^9...at n=4A012769a(n) = 3*a(n-1) - 4*a(n-3), with a(0)=1, a(1)=2, a(2)=4, a(3)=9.at n=15A136298a(0)=0, a(1)=1, a(n) = min{4 a(k) + (4^(n-k)-1)/3, k=0..(n-1)} for n>=2.at n=30A259665