A084639 - cp's OEIS frontend

A084639 Expansion of x(1+2x)/((1+x)(1-x)(1-2*x)).

n	a(n)
0	0
1	1
2	4
3	9
4	20
5	41
6	84
7	169
8	340
9	681
10	1364
11	2729
12	5460
13	10921
14	21844
15	43689
16	87380
17	174761
18	349524
19	699049
20	1398100
21	2796201
22	5592404
23	11184809
24	22369620
25	44739241
26	89478484
27	178956969
28	357913940
29	715827881
30	1431655764
31	2863311529
32	5726623060
33	11453246121

[0, 1, 4, 9, 20, 41, 84, 169, 340, 681, 1364, 2729, 5460, 10921, 21844, 43689, 87380, 174761, 349524, 699049, 1398100, 2796201, 5592404, 11184809, 22369620, 44739241, 89478484, 178956969, 357913940, 715827881, 1431655764, 2863311529, 5726623060, 11453246121]

cp's OEIS Frontend

A084639 Expansion of x(1+2x)/((1+x)(1-x)(1-2*x)).

Table of values

List of values

cp's OEIS Frontend

A084639 Expansion of x*(1+2*x)/((1+x)*(1-x)*(1-2*x)).

Table of values

List of values

A084639 Expansion of x(1+2x)/((1+x)(1-x)(1-2*x)).