A209399 - cp's OEIS frontend

A209399 Number of subsets of {1,...,n} containing two elements whose difference is 3.

n	a(n)
0	0
1	0
2	0
3	0
4	4
5	14
6	37
7	83
8	181
9	387
10	824
11	1728
12	3584
13	7360
14	15032
15	30571
16	61987
17	125339
18	252883
19	509294
20	1024300
21	2057848
22	4130724
23	8285758
24	16610841
25	33285207
26	66673209
27	133512759
28	267294832
29	535025408
30	1070755840
31	2142652160
32	4287149680
33	8577285255

[0, 0, 0, 0, 4, 14, 37, 83, 181, 387, 824, 1728, 3584, 7360, 15032, 30571, 61987, 125339, 252883, 509294, 1024300, 2057848, 4130724, 8285758, 16610841, 33285207, 66673209, 133512759, 267294832, 535025408, 1070755840, 2142652160, 4287149680, 8577285255]

cp's OEIS Frontend

A209399 Number of subsets of {1,...,n} containing two elements whose difference is 3.

Table of values

List of values