A328002 - cp's OEIS frontend

A328002 a(n) = 2^n * Sum_{k=0..n} Product_{j=1..k} (2/j)^((-1)^j).

n	a(n)
0	1
1	3
2	8
3	22
4	50
5	130
6	280
7	700
8	1470
9	3570
10	7392
11	17556
12	36036
13	84084
14	171600
15	394680
16	802230
17	1823250
18	3695120
19	8314020
20	16812796
21	37505468
22	75716368
23	167657672
24	338019500
25	743642900
26	1497686400
27	3276189000
28	6592494600
29	14348370600
30	28851858720
31	62512360560

[1, 3, 8, 22, 50, 130, 280, 700, 1470, 3570, 7392, 17556, 36036, 84084, 171600, 394680, 802230, 1823250, 3695120, 8314020, 16812796, 37505468, 75716368, 167657672, 338019500, 743642900, 1497686400, 3276189000, 6592494600, 14348370600, 28851858720, 62512360560]

cp's OEIS Frontend

A328002 a(n) = 2^n * Sum_{k=0..n} Product_{j=1..k} (2/j)^((-1)^j).

Table of values

List of values