A047653 - cp's OEIS frontend

A047653 Constant term in expansion of (1/2) * Product_{k=-n..n} (1 + x^k).

n	a(n)
0	1
1	2
2	4
3	10
4	26
5	76
6	236
7	760
8	2522
9	8556
10	29504
11	103130
12	364548
13	1300820
14	4679472
15	16952162
16	61790442
17	226451036
18	833918840
19	3084255128
20	11451630044
21	42669225172
22	159497648600
23	597950875256
24	2247724108772
25	8470205600640
26	31991616634296
27	121086752349064

[1, 2, 4, 10, 26, 76, 236, 760, 2522, 8556, 29504, 103130, 364548, 1300820, 4679472, 16952162, 61790442, 226451036, 833918840, 3084255128, 11451630044, 42669225172, 159497648600, 597950875256, 2247724108772, 8470205600640, 31991616634296, 121086752349064]

cp's OEIS Frontend

A047653 Constant term in expansion of (1/2) * Product_{k=-n..n} (1 + x^k).

Table of values

List of values