A123007 - cp's OEIS frontend

A123007 Expansion of x(1+x)/(1 -2x -9*x^2).

n	a(n)
1	1
2	3
3	15
4	57
5	249
6	1011
7	4263
8	17625
9	73617
10	305859
11	1274271
12	5301273
13	22070985
14	91853427
15	382345719
16	1591372281
17	6623856033
18	27570062595
19	114754829487
20	477640222329
21	1988073910041
22	8274909821043
23	34442484832455

[1, 3, 15, 57, 249, 1011, 4263, 17625, 73617, 305859, 1274271, 5301273, 22070985, 91853427, 382345719, 1591372281, 6623856033, 27570062595, 114754829487, 477640222329, 1988073910041, 8274909821043, 34442484832455]

cp's OEIS Frontend

A123007 Expansion of x(1+x)/(1 -2x -9*x^2).

Table of values

List of values

cp's OEIS Frontend

A123007 Expansion of x*(1+x)/(1 -2*x -9*x^2).

Table of values

List of values

A123007 Expansion of x(1+x)/(1 -2x -9*x^2).