x - x^3/3! + x^5/5! - ... + (-1)^n*x^(2n+1)/(2n+1)! has 2a(n)+1 real roots.

Terms

a(0) =0a(1) =1a(2) =0a(3) =1a(4) =2a(5) =1a(6) =2a(7) =3a(8) =2a(9) =3a(10) =2a(11) =3a(12) =4a(13) =3a(14) =4a(15) =3a(16) =4a(17) =5a(18) =4a(19) =5a(20) =6a(21) =5a(22) =6a(23) =5a(24) =6a(25) =7a(26) =6a(27) =7a(28) =8a(29) =7