A282701 - cp's OEIS frontend

A282701 a(n) = maximal number of real roots of any of the polynomials c_0 + c_1x + c_2x^2 + ... + c_n*x^n where the coefficients c_i are -1, 0, or 1, c_0 != 0, and c_n != 0.

n	a(n)
0	0
1	1
2	2
3	3
4	2
5	3
6	4
7	5
8	4
9	5
10	4
11	5
12	6
13	7
14	6
15	7
16	6
17	7
18	8
19	7
20	8
21	7

[0, 1, 2, 3, 2, 3, 4, 5, 4, 5, 4, 5, 6, 7, 6, 7, 6, 7, 8, 7, 8, 7]