A049897 - cp's OEIS frontend

A049897 a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 4.

n	a(n)
1	1
2	1
3	4
4	5
5	10
6	16
7	33
8	69
9	138
10	208
11	452
12	921
13	1848
14	3701
15	7403
16	14809
17	29618
18	44428
19	96262
20	196226
21	394305
22	789537
23	1579543
24	3159330
25	6318730
26	12637529
27	25275094
28	50550205
29	101100416
30	202200837
31	404401675
32	808803353
33	1617606706

[1, 1, 4, 5, 10, 16, 33, 69, 138, 208, 452, 921, 1848, 3701, 7403, 14809, 29618, 44428, 96262, 196226, 394305, 789537, 1579543, 3159330, 6318730, 12637529, 25275094, 50550205, 101100416, 202200837, 404401675, 808803353, 1617606706]

cp's OEIS Frontend

A049897 a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 4.

Table of values

List of values