A026644 - cp's OEIS frontend

A026644 a(n) = a(n-1) + 2*a(n-2) + 2, for n>=3, where a(0)= 1, a(1)= 2, a(2)= 4.

n	a(n)
0	1
1	2
2	4
3	10
4	20
5	42
6	84
7	170
8	340
9	682
10	1364
11	2730
12	5460
13	10922
14	21844
15	43690
16	87380
17	174762
18	349524
19	699050
20	1398100
21	2796202
22	5592404
23	11184810
24	22369620
25	44739242
26	89478484
27	178956970
28	357913940
29	715827882
30	1431655764
31	2863311530
32	5726623060

[1, 2, 4, 10, 20, 42, 84, 170, 340, 682, 1364, 2730, 5460, 10922, 21844, 43690, 87380, 174762, 349524, 699050, 1398100, 2796202, 5592404, 11184810, 22369620, 44739242, 89478484, 178956970, 357913940, 715827882, 1431655764, 2863311530, 5726623060]

cp's OEIS Frontend

A026644 a(n) = a(n-1) + 2*a(n-2) + 2, for n>=3, where a(0)= 1, a(1)= 2, a(2)= 4.

Table of values

List of values