A075111 - cp's OEIS frontend

A075111 a(n) = Sum_{i=0..floor(n/2)} (-1)^(i+floor(n/2))*T(2i+e), where T(n) are tribonacci numbers (A000073) and e = (1/2)(1-(-1)^n).

n	a(n)
0	0
1	1
2	1
3	1
4	3
5	6
6	10
7	18
8	34
9	63
10	115
11	211
12	389
13	716
14	1316
15	2420
16	4452
17	8189
18	15061
19	27701
20	50951
21	93714
22	172366
23	317030
24	583110
25	1072507
26	1972647
27	3628263
28	6673417
29	12274328
30	22576008
31	41523752
32	76374088
33	140473849
34	258371689

[0, 1, 1, 1, 3, 6, 10, 18, 34, 63, 115, 211, 389, 716, 1316, 2420, 4452, 8189, 15061, 27701, 50951, 93714, 172366, 317030, 583110, 1072507, 1972647, 3628263, 6673417, 12274328, 22576008, 41523752, 76374088, 140473849, 258371689]

cp's OEIS Frontend

A075111 a(n) = Sum_{i=0..floor(n/2)} (-1)^(i+floor(n/2))*T(2i+e), where T(n) are tribonacci numbers (A000073) and e = (1/2)(1-(-1)^n).

Table of values

List of values