A106519 - cp's OEIS frontend

A106519 a(n) = (2/n)binomial(2n-2, n-1) - (1/(2n))Sum_{d|n} Moebius(d)binomial(2n/d, n/d).

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	9
7	19
8	58
9	160
10	499
11	1527
12	4940
13	16001
14	53187
15	178305
16	606330
17	2079863
18	7203864
19	25138879
20	88367780
21	312577245
22	1112119079
23	3977502767
24	14294207172
25	51596165898
26	186998138529
27	680272336906
28	2483341820512
29	9094756956909

[1, 1, 1, 2, 3, 9, 19, 58, 160, 499, 1527, 4940, 16001, 53187, 178305, 606330, 2079863, 7203864, 25138879, 88367780, 312577245, 1112119079, 3977502767, 14294207172, 51596165898, 186998138529, 680272336906, 2483341820512, 9094756956909]

cp's OEIS Frontend

A106519 a(n) = (2/n)binomial(2n-2, n-1) - (1/(2n))Sum_{d|n} Moebius(d)binomial(2n/d, n/d).

Table of values

List of values

cp's OEIS Frontend

A106519 a(n) = (2/n)*binomial(2*n-2, n-1) - (1/(2*n))*Sum_{d|n} Moebius(d)*binomial(2*n/d, n/d).

Table of values

List of values

A106519 a(n) = (2/n)binomial(2n-2, n-1) - (1/(2n))Sum_{d|n} Moebius(d)binomial(2n/d, n/d).