A049915 - cp's OEIS frontend

A049915 a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2 and a(3) = 4.

n	a(n)
1	1
2	2
3	4
4	5
5	7
6	17
7	31
8	50
9	67
10	182
11	361
12	710
13	1387
14	2642
15	4756
16	7580
17	10222
18	28022
19	56041
20	112070
21	224107
22	448082
23	895636
24	1789340
25	3573742
26	7127042
27	14170036
28	28004060
29	54666862
30	103996022
31	187115026
32	298238090
33	402234112

[1, 2, 4, 5, 7, 17, 31, 50, 67, 182, 361, 710, 1387, 2642, 4756, 7580, 10222, 28022, 56041, 112070, 224107, 448082, 895636, 1789340, 3573742, 7127042, 14170036, 28004060, 54666862, 103996022, 187115026, 298238090, 402234112]

cp's OEIS Frontend

A049915 a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2 and a(3) = 4.

Table of values

List of values